Making a useful earpiece out of the Magic Mouth spell

**Baphomet** · 2022-05-12, 11:31 PM (ISO 8601)

There was a previous write-up on this forum concerning potential creative uses of the Magic Mouth spell. Now I'm in a campaign where I'm playing an Artificer, and I have given some serious thought to the sort of shenanigans that the spell could reasonably allow me to get up to without pissing off the DM too much. Though the home security potential described in the thread is phenomenal, unfortunately we don't really have a "home base" of any sort, nor does it seem that we'll be likely to. I'll need something portable. This object should solve three main problems that come up frequently in the campaign: nobody ever knows what time it is, creatures keep sneaking up on us, and we don't have an easy way to communicate without being overheard.

This should be the end result:

The Traveler's Earpiece
Wondrous Item, uncommon
The Traveler's Earpiece appears to be a small blob of iron wrapped in leather strips, roughly the shape and size of a human ear hole. Protruding from the top of the blob is a flexible metal wire also wrapped in leather, allowing the object to be clipped to the ear of any small or medium humanoid with ears, and oriented in a way that would seem to encourage it to be worn on the left ear. Along the side of the blob is a small vertical protrusion under the leather. The whole object appears to be crudely-constructed with cheap, common materials and little concern for the aesthetic quality of the craftsmanship.

The item has three main functions. The second and third functions are "secret" and can only be activated by creatures carrying the earpiece's mark, which marks them as an ally. The earpiece's mark is a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball". The three functions are:

A clock. Whenever a creature carrying the earpiece speaks the words "current time", the earpiece will whisper the current hour and minute of the day. Days are measured in 24-hour increments from the last time that the clock was set to midnight. A creature carrying the earpiece can set the clock to midnight by drawing a picture of an hourglass with the words "SET CLOCK MIDNIGHT" on it, touching a finger to the picture, and speaking the words "set clock midnight".
A creature scanner. To activate this feature, speak the words "start scanner". The earpiece then whispers the direction towards any creature within 30 feet. Directions are provided in terms of hours, with "twelve o'clock" corresponding to the direction the creature's face is pointing if wearing the earpiece on their left ear, "3 o'clock" being directly to the left of that, "6 o'clock" being behind, etc. The earpiece will not report the presence of any creatures of tiny size or smaller, creatures bearing the earpiece's mark, or creatures that are both invisible and inaudible. The earpiece then repeats this function every round (6 seconds) until you speak the words "stop scanner".
A whispered conversation listener. Activate this feature by speaking the words "start listener". The earpiece then begins to repeat any words spoken at a whispered volume or lower by any other creature in 30 feet, ceasing when you speak the words "stop listener". The words are spoken in monotone, lacking any inflection or changes in volume in the original utterance.

To create a Traveler's earpiece, you need this:

660 gp worth of honeycomb and jade dust, suitable for casting Magic Mouth 66 times.
A bit of scrap metal. If you can't just buy raw iron, a single 2 gp dagger probably has enough metal in it to make a dozen of these.
A bit of flexible wire about 3 inches long.
A small lump of soft wax, about half the size of a grape.
A few small scraps of leather.
Needle and thread.
A flat clean work surface, such as a platter or mirror.
Tweezers.
54 grains of sand (or more, just in case).
Access to the equipment necessary to shape metal, and someone willing and able to use it.

Ritual casting the spells will take a total of 12 hours and 6 minutes. Crafting the components into their finished form is something that a normal person could reasonably accomplish in 3-4 hours. I go over the construction process in detail below, but first I want to talk about the spell that makes this all possible: Magic Mouth.

The thread I linked at the top does a fantastic job of explaining the basics of using the spell to write magical programs, and you should really give it a read if you haven't already. There can be some disagreement about what the spell is capable of because the description is a little vague about some parts. Depending on your interpretation, the spell can range in utility from "useless for anything but pranks" to "supercomputer with localized omniscience". Below, I'm going to outline what I think are reasonable rulings about what it does. If you are a DM and you agree with these rulings, then your players can make this object.

Spoiler: The Rules

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I'll start with a summary of the spell as written. Magic Mouth is a 2nd level illusion spell available to Artificers, Bards, and Wizards. It takes 1 minute to cast normally or 11 minutes to cast ritually, and each casting consumes 10 gp worth of honeycomb and jade dust. You define a triggering circumstance for the spell and cast it on any object (within 30 feet). You also include a message, which is defined when you "speak the message, which must be 25 words or less, though it can be delivered over as long as 10 minutes" as part of casting the spell. Thereafter, the object will recite the message "in your voice and at the same volume you spoke" from an illusory mouth that appears when the triggering circumstance occurs. If the object has something that looks like a face, the mouth appears there and makes it look like the face is talking. You can decide whether the message is only recited once or if it repeats every time the triggering condition happens (but every Magic Mouth spell used to create the Traveler's Earpiece is of the latter variety) and the spell lasts until it is dispelled. The triggering circumstance "can be as general or as detailed as you like, though it must be based on visual or audible conditions that occur within 30 feet of the object." The spell text then gives two examples of valid triggering circumstances, "any creature moves within 30 feet of the object" and "a silver bell rings within 30 feet of [the object]." That's pretty much all the guidance it gives.

Question 1
The biggest major question is, "What is the spell able to see and hear?" The text doesn't say it makes Perception checks to see and hear things. Whose vision is its visual detection ability based on? A blind Grimlock? A Couatl with Truesight? What about hearing? Can it only hear what a human hears, or can it hear well enough to effectively have the blingsight of a bat or the tremorsense of a Bulette? Is an illusion a "visual condition"? Can it detect visual conditions that are too small for the human eye, like the presence of bacteria and atoms? Is the spell's ability to detect visual and audible conditions blocked by line of effect? What about water or glass?

The spell doesn't say these things, so we have to make reasonable assumptions. First, I would not assume that the spell has "supernatural" vision. It can't see infrared, it can't see into the ethereal plane, it can't see things that are invisible. I would also assume that it has the visual "perspective" of a standard medium creature, and not allow it to "zoom in" to see things like cells and atoms. As for tremorsense, blindsight, and darkvision, I'd leave that up to the individual DM; the Traveler's Earpiece doesn't require those things to be true, but they affect its potency. I will say that Darkvision seems reasonable to me if only because 6 out of the 9 player races in the PHB have it.

However, I would assume that the spell's detection range is not blocked by obstructions. Ruling otherwise would seem to invalidate what I would guess are intended uses for the spell. If you can cast MM on an object, put that object in your pocket, and still have it go off based on a trigger outside your pocket, then it must be able to see through your clothes. If you are a DM balking at that idea, you could consider the wording of other "detection" spells like Detect Magic as a house rule: "The spell can penetrate most barriers, but it is blocked by 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt."

That said, I would definitely not assume that the spell is seeing or hearing the way we do. It detects visual or audible conditions inside its range, full stop. On the one hand, that means that an illusion of a creature still counts as a creature for the spell because it provides the "visual condition" of one. On the other hand, it also means that a creature that rolled 44 for Stealth also counts as a creature for the spell, because even though their "visual condition" is hard to see, it's still present. In other words, even thought the spell doesn't make Perception checks, I would allow it to perceive any audible or visible conditions that could conceivably be detected successfully with a Perception check.

Question 2
Another major question is, "What is an allowable message?" The fact that the message is restricted to 25 words or less sends mixed signals about the intent when placed next to the fact that it can be spoken over up to 10 minutes. Can you fill that time by pausing between words, or do you have to speak slowly? Zero words is 25 or less; can the message contain no words? Can it be 10 minutes of screaming? What about 10 minutes of silence?

I would base my decision on the words "speak the message". You can speak a sound that isn't a word, but you can't speak silence, and silence isn't a message. However, I'd also treat it like plugging in an audio recording. You speak some message, and you decide where the part that counts as your output begins and ends. It can have leading or trailing silence, as long as the final selection contains a sound, is 10 minutes or less, and doesn't contain more than 25 words. I would also think that it's reasonable to, as an example, speak the word "bridge" aloud but specify that only the sound after the "bri" part counts as your intended message. That's not strictly necessary for the Traveler's Earpiece to work, but would make some messages easier to record.

It's also worth noting that each casting of Magic Mouth definitely outputs the same message spoken in the same way every time it is triggered. You can't vary the message, even its volume or intonation, based on the way it was triggered.

Question 3
Next, we should clarify some things about the target for the spell. The spell only says that it affects an object. I see no reason that couldn't include something tiny, like a single grain of sand. The spell only definitely understands a few things about its target. First, it knows the visual and audible conditions produced by the object. Second, because the example triggers refer to "this object", we know that the spell can unambiguously identify the object it is cast on. Third, because the spell behaves differently depending on whether or not the target object has "a mouth or something that looks like a mouth", we know it can identify facial features.

As a point related to the above, there was disagreement in other threads about whether or not the "combining magical effects" rule applies to this spell. To be safe, I am going to assume that it does. The construction plans for the Traveler's Earpiece will not involve any components with multiple Magic Mouth spells on the same object.

Question 4
The next major question to answer is, "what does the spell understand?" The text's two examples, "a creature moves within 30 feet of this object" and "a silver bell rings within 30 feet of this object", give us some starting points. Where visual conditions are concerned, these tell us that the spell is able to parse what it's seeing and describe it with abstract concepts. You don't have to provide a comprehensive description of every visual quality of a creature, you can just say "a creature" and the spell knows what you mean. Similarly, the spell could see a massive silver church bell or a tiny silver sleigh bell and understand that both of those objects are silver bells. Audible conditions are probably the same way, since the spell recognizes that the very different sounds produced by either of those bells counts as "ringing".

Armed with the text's two examples of what would be allowable triggers, I'm going to suggest some more things that I think would be reasonable, and what we can extrapolate about the spell's abilities from that.

Reasonable Assumptions
First, the ones directly related to the Traveler's Earpiece. These are the ones that a DM would need to agree with for the earpiece to function as intended.

"There are five silver bells within 30 feet of this object." This is simple but fundamental. This would imply that the spell understands numbers.
"A creature moves within 10 feet of this object." If the spell understands numbers and its own detection range, it can probably also recognize distances other than 30 feet. In fact, since the spell can't detect beyond its 30 foot range anyway, I'm going to assume the "within 30 feet of this object" part of the example triggers is superfluous.
"A silver bell rings twice." To understand that a bell is ringing for the second time, the spell would have to remember that the bell already rang once. Therefore, that would imply that the spell is able to remember things that happened previously. I would not assume that the spell can remember things that happened before it was cast, or that happened when the spell was more than 30 feet away.
"A silver bell rang exactly 15 seconds ago." If the spell understands numbers and can remember past events, it must have a concept of time. It makes sense to me that it could make measurements of that time, like counting out seconds.
"A creature speaks the word 'Beetlejuice'." The spell can likely use visual and audible conditions both to identify a word that is spoken and identify that it was spoken by a creature (instead of, for example, another Magic Mouth spell.)
"A creature whispers the word 'Beetlejuice'." If the spell can definitively categorize the many different soundwaves made by bells under the word "ring" then it can probably differentiate between a word that is whispered from one that is spoken at a normal volume.
"The total number of times that the word 'Beetlejuice' has been spoken by all creatures is an integer multiple of 3." This is getting into more complex territory, but if the spell understands vocabulary well enough to match images and sound to words describing those images and sounds, and it specifically allows triggers to be as "detailed as you like", then it can probably also evaluate logical or mathematical statements that you can describe using words it understands.
"This object is facing a silver bell." I'm including this because I think it should be allowed with a caveat. Since I mentioned above that the spell knows whether or not its target object has a face, I'm only allowing Magic Mouth spells to refer to their target objects' facing direction if the object literally has a face on it. A face has an easily-understood up, down, left, right, forward, and backward. Without one, the reference frame is ambiguous. This imposes size restrictions on objects that have triggers referring to their relative facing directions, since it's unfeasible to carve a face into something like a grain of sand.

Those are the only strictly-necessary rulings for the Traveler's Earpiece. If your DM agrees to these rulings, then you have all the tools you need to make it. If that's all you're interested in doing, you can skip the rest of this spoiler box.

However, I'm going to list some more examples along with whether I think they should be allowable. This is both for the purposes of giving potential DMs reading this thread an idea of what kinds of questions they will need to answer if their players create this object, and to provide understanding of the ruleset for the purposes of developing additional functionality for this object by interested members of the community.

"A human moves." This seems reasonable, because if the spell understands what visual or audible conditions qualify something to be a "creature", it can probably do the same for a human. However, this would also trigger for other things with visual or audible conditions like a human, such as an illusion or a polymorphed creature.
"A werewolf in human form moves." This does not seem reasonable, because there aren't visual or audible conditions that differentiate a werewolf in human form from a regular human.
"I move." I would not assume that this is reasonable, because the object doesn't know who I am.
"Strahd von Zarovich moves." Similarly to the above, I would not assume that this is valid. The line between a generally-understood valid categorization word like "creature" and something specific like the name of a particular person is hard to definitively draw. I would assume the spell only understands words that would be allowed in Scrabble, unless the word is defined within the trigger itself.
"A creature moves, and that creature is not on the ignore list. A creature is added to the ignore list when it speaks the words 'add me to the ignore list' while touching this object." I wouldn't allow this. The reason is pretty complicated, but it boils down to the fact that it relies on the spell's memory of its own internal logic rather than a visual or audible condition. To elaborate-
"A creature moves, and that creature is not on the ignore list. A creature is on the ignore list when it is carrying a piece of parchment with 'add me to the ignore list' written on it." I would allow this, because all of the logic dictating whether or not a creature should be ignored can be computed using only past or present visual/audible conditions. To put it in programming terms, I assume that the trigger is like a function being called repeatedly in a loop. The function has one argument, and it's a timestamped list of all visual and audible conditions that have occurred in its detection range since the spell was cast. It's okay to define new terms like variables as long as they are local to the function itself. They're deleted when the function terminates (i.e. when it decides whether or not it should trigger at the present moment) and the function doesn't know what they were the next time it's called.
"A creature speaks the words 'start loop' or an illusory mouth appeared on this object exactly 15 seconds ago." The spell both detects and creates visual and audible circumstances. I see no reason that Magic Mouth spells could not trigger other Magic Mouth spells, or even trigger themselves.
"A creature speaks the words 'start loop' or an illusory mouth appears on this object." The mouth appears instantaneously when the triggering circumstance is detected. Hypothetically this would lead to infinite triggerings every second. For the sake of not lagging out the universe in an unexitable loop, I'll assume that the spell stops checking for the triggering circumstance while it's in the process of speaking its output, so each spell never creates more than one mouth at a time. There must be a delay between triggerings that is at least as long as something that qualifies as a spoken message.
[The entire instruction set for a modern CPU, designed to output in a series of beeps that encode binary signals.] I wouldn't allow this. The general rule of thumb I'm following here is, "if you can't clearly speak both the output and the trigger aloud in the casting time of the spell, something is too complicated." Yes, that limits you to simpler instructions if you cast the spell normally instead of ritually, but that seems acceptable to me. It never really made much sense that you could cast the spell in 1 minute and have it play a 10 minute recording of your voice, anyway.

With that out of the way, next comes the assembly instructions. I'm putting that in the next post along with an important message.

**Baphomet** · 2022-05-13, 09:42 PM (ISO 8601)

Before the instructions, I have a very important message about how I expect these instructions to be used.

These instructions are not intended to be carried out in character step by step at your table. If you are a player and you want to make this object, I encourage you to just show this thread to your DM and have them agree or disagree. If they agree, your character abstractly spends the time and resources, and then they have the item. Please do not bog down your table by reading out pages and pages of magical legalese, and do not expect your DM to be able to parse what this thing should do based on a verbal shotgun reading of all the "code" that makes it work. I'm only including the actual instruction manual for three reasons:

I want people who understand this to keep me honest and make sure I'm not overreaching. Everything in these instructions should adhere to the reasonable assumptions made above. I don't want to do something that I shouldn't reasonably be allowed to do. Likewise, I want to make sure that it will actually do what I said it should do in the item description at the top.
I want to prove that the necessary steps are actually achievable. There have been other threads in the past about the hypothetical potential of the Magic Mouth spell, but all the ones I've seen have had great discussions on the theory and then stopped short of providing an implementation. While a hypothetical magitech supercomputer is a fun thought experiment, I wanted to try to write up something that would be reasonable for a character to produce with the time and resources they would be likely to be able to spare in a real campaign, and that would provide a tangible utility in the course of an actual adventure.
With an actual blueprint, I can more definitively say what is required, what works, and what doesn't. This has already gone through several revisions where I reworded things to fix bugs. This could also allow interested members of the community see what might be added or how the existing object might be optimized.

Now, the instructions for assembly:

Spoiler: Instructions for Assembly

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This object requires 66 Magic Mouth spells, 54 of which will be cast on sand grains, while the other 12 will be cast on tiny, specially-constructed beads. In other words, several miniscule, easy-to lose objects. You probably want to ritually cast these spells, which means you'll spend 12 hours and 6 minutes on ritual casting alone, not to mention the time it takes to craft the object that houses all of the components. I would advise that you don't start with the spellcasting until everything else is ready, at which point you're going to want to do your work in a clean space where you will not be disturbed, and not stop working until you're finished. You want to minimize the amount of time where spilling a vial of sand means wasting hundreds of gp and hours of work.

So, the first step is to assemble your materials. I list them up top, but to reiterate, you will need:

660 gp worth of honeycomb and jade dust, suitable for casting Magic Mouth 66 times.
A bit of scrap metal. If you can't just buy raw iron, a single 2 gp dagger probably has enough metal in it to make a dozen of these.
A bit of flexible wire about 3 inches long.
A small lump of soft wax, about half the size of a grape.
A few small scraps of leather.
Needle and thread.
A flat clean work surface, such as a platter or mirror.
Tweezers.
54 grains of sand (or more, just in case).
Access to the equipment necessary to shape metal, and someone willing and able to use it.

Let's get the metalworking out of the way next. You'll want to hammer a small flat sheet of metal into a tall trapezoid shape, about an inch tall, three quarters of an inch wide at the base, a quarter inch wide at the top, and as thin as you can make it. Then you want to curl the sheet like a Frito. Put one end of the flexible wire inside the curl of the shortest edge and hammer it flat so the wire is held in place. It should end up looking something like this:

Next, create a thin rod about an inch long and as thin as you can reasonably make it. This will be the spindle that holds the beads that watch for nearby enemies. Before attaching it to the outside of the earpiece, we need to align it properly. Compare what you've got so far to the size and shape of your intended owner's ear. It should be a little small, because we haven't wrapped it in leather for padding yet. What you're trying to figure out is which way it naturally sits when worn, so you can more-or-less vertically align the spindle. When you think you've got a good handle on the direction, attach the bottom of the spindle to the outside of your Frito shape and bend it to align with the vertical direction.

Hammer out another thin rod of metal. Using a small sharp object, hammer three indentations in the tip of the rod, roughly in the shape of a face. Then flatten the bit right before the end, leaving the face on a small nub, and cut off the rest of the unflattened rod. Poke a hole in the center of the flat part large enough to fit over the spindle, then grind the flat part's edges into a circle. The result should look like this, but as small as you can make it:

Now make 11 more of these, giving you a total of 12 tiny flat "beads" with faces on them.

Only a bit more crafting work before you start casting spells. First fold a small leather scrap in half and sew two of the sides together, giving you a thin leather "pouch" a little smaller than the size of the indentation in your metal Frito. Then bend the wire roughly into the shape it would be when clipped onto the left ear, wrap that in leather strips, and secure them in place. Finally, prepare enough leather strips to fully wrap the rest of the exposed metal parts, plus some extra to tie the end off and to account for the added width when the beads are attached.

Finally, it's time for the spellcasting.

We'll deal with the beads first. These beads are going to whisper the numbers 1-12. They also each need to be fitted on the spindle in the correct orientation: 30 times their associated number in degrees clockwise from straight ahead. After casting the spell on each bead, I would recommend pinching off a tiny piece of wax and dabbing it onto the flat part of the bead, then putting it on the spindle in the correct orientation immediately. The wax should keep the beads from rotating too much. Also, since the face nubs probably take up more than 1/12th of the bead's circumference and are tall enough to potentially bump against beads above and below, I'd recommend doing them in a nonlinear order that spaces them out, for example: 1, 4, 7, 10, 2, 5, 8, 11, 3, 6, 9, 12.

We'll start with the number 1. Cast Magic Mouth on the first bead with these instructions:

Whisper "one" if any of the following 3 conditions are met, using the 5 definitions below them.
The 3 conditions:

clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.1 seconds ago, and the modulus of minuteCount and 720 is from 60 to 119 inclusive.
clockCallEvent is not undefined, and clockCallEvent occurred exactly 1.3 seconds ago, and the modulus of minuteCount and 60 is 1, 21, 31, 41, or 51.
All 5 of the following statements are true:

scannerStartTime is not undefined.
scannerStartTime is an integer multiple of 6000.
scannerStopTime is undefined or scannerStartTime is less than scannerStopTime.
scannerStartTime is less than the number of milliseconds since the last occurrence of this object not being carried by a creature that is also holding a securityKey.
At least one creature that is larger than tiny size and is not carrying a securityKey is located in a space inside a horizontal cylindrical sweep from -15 to 15 degrees of the direction this object is facing.
The 5 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".
"securityKey" is a type of physical object defined as a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
"scannerStartTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "start scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.
"scannerStopTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "stop scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.

There's a lot going on there; each of the main conditions could be merged into one large run-on sentence, but I tried to space things out and define terms beforehand for clarity. The instructions for the beads for the numbers 2, 3, and 5 will be similar enough that I don't feel the need to write them out. 4, 6, 7, 8, and 9 are slightly different, because those numbers can all pull double duty as the first half of a word ending in "teen". For example, the instructions on the Magic Mouth spell for the 4th bead would also have an extra condition added to the list:

clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.8 seconds ago, and the modulus of minuteCount and and 60 is 14.

The numbers 10, 11, and 12 are similar, except that they can't be the second half of a number. Here's the full instruction set for the 10th bead, and you can extrapolate the rest from there:

Whisper "ten" if any of the following 3 conditions are met, using the 5 definitions below them.
The 3 conditions:

clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.1 seconds ago, and the modulus of minuteCount and 720 is from 600 to 659 inclusive.
clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.8 seconds ago, and the modulus of minuteCount and 60 is 10.
All 5 of the following statements are true:

scannerStartTime is not undefined.
scannerStartTime is an integer multiple of 6000.
scannerStopTime is undefined or scannerStartTime is less than scannerStopTime.
scannerStartTime is less than the number of milliseconds since the last occurrence of this object not being carried by a creature that is also holding a securityKey, if any.
At least one creature that is larger than tiny size and is not carrying a securityKey is located in a space inside a horizontal cylindrical sweep from -15 to 15 degrees of the direction this object is facing.
The 5 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".
"securityKey" is a type of physical object defined as a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
"scannerStartTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "start scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.
"scannerStopTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "stop scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.

Once all of the beads are on the spindle in roughly the correct orientation and somewhat held in place with wax, it's time for the sand grains. You should have about a blueberry worth of wax left. Roll it into a ball and smoosh it on your work surface to make a concave disc shape. The wax is going to act as a sticky substrate that contains all of the sand grains and is sewn into the leather pouch we made earlier. Each time you finish casting the spell on a grain, smoosh that grain into the indentation in your wax. If something comes up and you have to quit before you're finished, store your sand-filled wax ball and your nonmagical sand in separate vials.

Here's the instructions for the sand grain that says 13, from which you can also derive the sand grain that says 15.

Whisper "thirteen" if clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.8 seconds ago, and the modulus of minuteCount and 60 is 13, using the following 2 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".

Next, "teen":

Whisper "teen" if clockCallEvent is not undefined, and clockCallEvent occurred exactly 1.3 seconds ago, and the modulus of minuteCount and 60 is 14, 16, 17, 18, or 19, using the following 2 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".

We'll finish up the number-related ones with 20, 30, 40, and 50. They're all pretty similar, and you can probably figure out the other ones based on the instructions for 20:

Whisper "twenty" if clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.8 seconds ago, and the modulus of minuteCount and 60 is from 20 to 29 inclusive, using the following 2 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".

You might be thinking, "Isn't the 0 at the beginning of the minutes from 1 to 9 also a number related one?" Sort of, but I'm going to lump that one in with a different group at the end, for reasons that should become obvious later. Now, we'll do the sand grain for "o'clock". We want this to come after any times ending in :00, as well as any directional cues from the creature detector.

Whisper "o'clock" if either of the following 2 conditions are met, using the 5 definitions below them.
The 2 conditions:

clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.8 seconds ago, and minuteCount is an integer multiple of 60.
All 5 of the following statements are true:

scannerStartTime is not undefined.
The modulus of scannerStartTime and 6000 is 700.
scannerStopTime is undefined or scannerStartTime is less than scannerStopTime.
scannerStartTime is less than the number of milliseconds since the last occurrence of this object not being carried by a creature that is also holding a securityKey, if any.
At least one creature is present that is larger than tiny size and is not carrying a securityKey.
The 5 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".
"securityKey" is a type of physical object defined as a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
"scannerStartTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "start scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.
"scannerStopTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "stop scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.

Next is "AM", so that "PM" will be self-explanatory:

Whisper "AM" if clockCallEvent is not undefined, and clockCallEvent occurred exactly 20 seconds ago, and the modulus of minuteCount and 1440 is less than 720, using the following 2 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".

If you're keeping track, we've got Magic Mouths for the numbers 1-13, 15, "teen", 20, 30, 40, 50, "o'clock", "AM", and "PM", for a total of 22 spells total. With that, we've covered almost everything related to both the clock and the creature detector functions. So, you might be wondering what the other 44 spells and sand grains are for. Well, the original thread for this suggested that you could recreate speech with 26 magic mouths: one for each letter in the alphabet. I disagree. As mentioned in the rules section, you can't change the way that a magic mouth says its message based on the nature of its triggering event, meaning you'd have to say each letter of the alphabet one way. However, many letters are overloaded to cover multiple different pronunciations. For example, the "T" in "tank" is different from the one in "thank" and "nation". Pronounced letter-by-letter, "nation" would be pronounced "natty-on". In other words, you'd get a questionably-parseable garbled mess.

If we want to recreate speech using Magic Mouth, instead of using building blocks based on the visual symbolic representation of a word (AKA its spelling), we'd have to break the sounds into some sort of auditory building blocks based on the sounds composing the word when it is spoken. In other words, we need to use the phonemes. Phonemes vary by language, but they're basically the list of sounds that the language considers to be unique from one another. There is disagreement about how many there are in English, but the most common consensus I've seen is 44. If you want to go way down the rabbit hole, you could ask your DM how many phonemes there are in the Common Tongue of D&D instead, but I think 44 is probably a reasonable guess. Here's a list of their symbolic representations, along with what sounds they stand for, summarized from this site:

Spoiler: The 44 Phonemes

Show

b, as in bug or bubble
d, as in dad, add, or milled
f, as in fat, cliff, phone, enough, half, or often
g, as in gun, egg, ghost, guest, or prologue
h, as in hop or who
dʒ, as in jam, wage, giraffe, edge, soldier, or exaggerate
k, as in kit, cat, chris, accent, folk, bouquet, queen, rack, or box
l, as in live or well
m, as in man, summer, comb, column, or palm
n, as in net, funny, know, gnat, pneumonic, or mneumonic
p, as in pin or dippy
r, as in run, carrot, wrench, or rhyme
s, as in sit, less, circle, scene, psycho, listen, pace, or course
t, as in tip, matter, thomas, or ripped
v, as in vine, of, stephen, or five
w, as in wit, why, quick, or choir
z, as in zed, buzz, his, scissors, xylophone, or craze
ʒ, as in treasure, division, or azure
tʃ, as in chip, watch, future, action, or righteous
ʃ, as in sham, ocean, sure, special, pension, machine, conscience, or station
θ, as in thongs or math
ð, as in leather or this
ŋ, as in ring, pink, or tongue
j, as in you, onion, or hallelujah
æ, as in cat, plaid, or laugh
eɪ, as in bay, maid, weigh, straight, pay, foyer, filet, eight, gauge, mate, break, or they
e, as in end, bread, bury, friend, said, many, leopard, heifer, or aesthetic
i:, as in be, bee, meat, lady, key, phoenix, grief, ski, deceive, people, or quay
ɪ, as in it, england, women, busy, guild, gym, or sieve
aɪ, as in spider, sky, night, pie, guy, stye, aisle, island, height, or kite
ɒ, as in swan, honest, maul, slaw, or fought
oʊ, as in open, moat, bone, toe, sow, dough, beau, brooch, or sew
ʊ, as in wolf, look, bush, or would
ʌ, as in lug, monkey, blood, or double
u:, as in who, loon, dew, blue, flute, shoe, through, fruit, maneuver, or group
ɔɪ, as in join or boy
aʊ, as in now, shout, or bough
ə, as in about, ladder, pencil, dollar, honor, or augur
eəʳ, as in chair, dare, pear, where, their, or prayer
ɑ:, as in arm or arc
ɜ:ʳ, as in bird, term, burn, pearl, word, journey, or myrtle
ɔ:, as in paw, ball, fork, poor, fore, board, four, taught, war, bought, or sauce
ɪəʳ, as in ear, steer, here, or tier
ʊəʳ, as in cure or tourist

If we have magic mouth spells that say each of those in the same order as someone else says them, even if they are spoken without nuanced intonation or emphasis, the end result would still be understandable.

Now, I mentioned earlier that we were covering the 0 in (HOUR):0(MINUTE) times later. That's because the time 12:01 isn't spoken as "twelve zero one", it's "twelve oh one". But, "oh" is just a single phoneme: oʊ. Rather than spend another 11 minutes and 10 gp, we'll just make that phoneme special. The rest of them will all be similar. Here's the instructions for the Magic Mouth spell covering the first one, "b", as an example:

Whisper "b" if all of the following 4 conditions are met, using the 4 definitions below them.
The 4 conditions:

listenerStartTime is not undefined.
listenerStopTime is undefined or listenerStartTime is less than listenerStopTime.
listenerStartTime is less than the number of milliseconds since the last occurrence of this object not being carried by a creature that is also holding a securityKey.
speakTime is not undefined, and a creature that is not carrying this object whispered any intonation of the "b" phoneme in the previous speakTime milliseconds.
The 4 definitions:

"securityKey" is a type of physical object defined as a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
"listenerStartTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "start listener" while holding both this object and a securityKey. It is undefined if this has not occurred.
"listenerStopTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "stop listener" while holding both this object and a securityKey. It is undefined if this has not occurred.
"speakTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a mouth appearing on this object. It is defined as listenerStartTime if this has not occurred.

Now, last but not least, the final Magic Mouth spell:

Whisper "oʊ" if either of the following 2 conditions are met, using the 6 definitions below them.
The 2 conditions:

clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.8 seconds ago, and the modulus of minuteCount and 60 is from 1 to 9 inclusive.
All 4 of the following statements are true:

listenerStartTime is not undefined.
listenerStopTime is undefined or listenerStartTime is less than listenerStopTime.
listenerStartTime is less than the number of milliseconds since the last occurrence of this object not being carried by a creature that is also holding a securityKey.
speakTime is not undefined, and a creature that is not carrying this object whispered any intonation of the "oʊ" phoneme in the previous speakTime milliseconds.
The 6 definitions:

"clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
"minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".
"securityKey" is a type of physical object defined as a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
"listenerStartTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "start listener" while holding both this object and a securityKey. It is undefined if this has not occurred.
"listenerStopTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "stop listener" while holding both this object and a securityKey. It is undefined if this has not occurred.
"speakTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a mouth appearing on this object. It is defined as listenerStartTime if this has not occurred.

And with that, we're done casting spells!

Once you finish, close up the wax ball so none of the sand grains are sitting on its surface, then stuff it inside the leather pouch you made earlier. Sew that shut and wedge it inside the inner curvature of the metal Frito. Double-check the orientation of the beads, then wrap the whole assembly tightly in leather strips. They should be snug enough to prevent the beads from rotating. Secure the ends in place firmly, and you're done! There's only two things left to do. First, tear off as many scraps of parchment as you have party members (including yourself), use ink to draw a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball" on all of them, and distribute them. Then, next midnight, draw a picture of an hourglass labeled "SET CLOCK MIDNIGHT", touch the drawing with one finger while wearing the earpiece, and say "set clock midnight".

And there you have it!

Thoughts? Optimizations? Any other cool features I could reasonably add without adding too many new parts?

**Willowhelm** · 2022-05-13, 10:57 PM (ISO 8601)

I had a lot of fun thinking about the uses and abuses of magic mouth a while back. I partially wrote a guide but never posted it. I did post this thread though:

https://forums.giantitp.com/showthre...-mouth-rulings

Here are my thoughts on your earpiece:

This requires DM buy in. If your DM is happy to do this, you can probably skip the design/casting etc and just ballpark a cost and get a magic item that does what you want.

If you really want to take the magic mouth stuff to it's final form - you can make a supercomputer/AI with infinite processor speed, full 360 audio and visual recording, and infinite memory with a handful of castings (depends on exact rulings - potentially just one). The hardest part (requiring the most castings/cost) is taking the binary output from that and making it useful (converting to sound).

I enjoyed the thought experiment and i'd be happy to share how it works but, as with your earpiece, it isn't really practical in-game. You can't say "the spell would let me" and get your cool item without the DM. With the DM you can skip the entire Magic Mouth part and just get the cool item.

The original thread was... limited in its approach. The challenges raised in it are trivial to overcome and extrapolating "reasonable" rulings (as in my thread) soon gives you a game-breakingly powerful spell. You can replace multiple magic items and bring about the digital revolution in your world. Pair it up with some tiny servants (or similar) and you have AI controlled robots. It really is just ludicrously exploitable.

But it isn't practical in real play. Just make a custom magic item with your DM and agree on a reasonable cost.

-------

Edit to avoid double post:

I'm failing to see any reason why the beads have the physical design they do. The earpiece should be comfortable to wear and place the mouths near enough to be audible - other than than there doesn't seem to be a reason for their form? If the DM agrees that you can cast repeatedly on the same object (the spell doesn't restrict this) then you can just have a nice earring as the target for all the castings.

I'd avoid the constant repetition of your time sync and scanner mode enable/disable text. There's no reason to copy/paste that so many times. I'd just say "is in scanner mode" and "scanner mode enabled by <action>"

Other than for flavour i don't see the reliance on specific images and physical items.

Your magic mouth already has the concept of time and state (this happened x seconds since y action was taken). That means your conditions can be things like "at least one creature was present that was larger than tiny size and is not on the ignore list" and "a creatures is on the ignore list if i have pointed at it and said 'ignore'". (Potentially you can add them by name even if they're not present, or add/remove entire creature types and other conditions.)

---

In my design i have a single object function as the "smart" part of the system. It is essentially a fully functional computer with audio/visual input and a single method of output. I make that output a stream of binary (open/closed mouth or making sound/not making sound) and then i have a separate set of objects transform that binary into something useful. One option is the phoneme set you have - each set to trigger when seeing a specific binary output from the computer.

This setup allows you to have all your functionality and more. Not only clock time read aloud but days, dates, moon phase and whatever else. Not only creature directions but creature types etc etc.

It's also trivial to make segment displays (white objects, black inside mouth) to have a digital watch or (poor quality) pixel output for a black and white screen.

Contrary to what is said in the arcane programmer thread, getting physical movement from using arcane lock is totally possible with no perpetual motion issues so that opens up a whole other avenue of options.

I really should just finish my guide...

**Baphomet** · 2022-05-16, 01:36 PM (ISO 8601)

Originally Posted by Willowhelm

I had a lot of fun thinking about the uses and abuses of magic mouth a while back. I partially wrote a guide but never posted it. I did post this thread though:

That's a great read too! You hit a couple points I didn't think of. I was also surprised to see so many people disagreeing with what I thought were clear-cut assumptions about the function of the spell.

The threads about this that I've seen so far, though, have all been theory and not implementation. That's what I was trying to do here.

Originally Posted by Willowhelm

This requires DM buy in. If your DM is happy to do this, you can probably skip the design/casting etc and just ballpark a cost and get a magic item that does what you want.

True. In my particular case, however, I have a DM that would be much more convinced by "the rules say I can make this right now" than "I think it would be cool if I could have something like this." And (again, with my specific character in this specific campaign with my specific DM) it might even make sense that I would be the first person to come up with this since my character is likely the world's first and only Warforged. It seems reasonable that I would think about things like Magic Mouth in a way that nobody had before.

Originally Posted by Willowhelm

If you really want to take the magic mouth stuff to it's final form - you can make a supercomputer/AI with infinite processor speed, full 360 audio and visual recording, and infinite memory with a handful of castings (depends on exact rulings - potentially just one).

I'd love to see an attempted implementation of that!

Originally Posted by Willowhelm

extrapolating "reasonable" rulings (as in my thread) soon gives you a game-breakingly powerful spell. You can replace multiple magic items and bring about the digital revolution in your world.

I'm...not sure that's the case? At the end of the day, the earpiece I proposed up there has some shortcomings, and 660+gp per earpiece is not exactly "cheap". Depending on what your setting's magic item economy is like, there might be other magic items out there with a better value/cost ratio.

The rules I'm limiting myself to cover a lot of your other shortcuts, though if my DM ruled that I didn't need to follow those rules, they could absolutely make these simpler.

I'm only allowing a spell to use direction as part of the trigger if the object itself has a "face" on it. That's why the beads have the design they do. That's also why I don't just condense everything into the 44 phoneme triggers; all of them would need to know the directional information from all of the output words they are part of in the creature detector. 44 face-bearing beads is probably too large for an earpiece. Although, I suppose I could have some sort of uniquely-identifiable orientation-defining component that they all refer back to, except that also-
-I am not using any triggers that couldn't reasonably be said aloud in the time it takes to cast the spell. I didn't state that in the OP, which I will now fix. That probably rules out specifically timing repeated phoneme triggers to sound out all of the non-phoneme MMs. EDIT: actually, I guess it doesn't, at least for these purposes. I give an example in the spoiler below.
I'm not defining internal variables. I don't think those count as an audible or visual trigger. That's why I'm repeating the conditions under which those variables would be defined every time I need to use them. If the DM allows internal memory like that, it would also greatly simplify things.
I'm assuming the "combining magical effects" rule prevents multiple MMs on the same object. I know there's disagreement on this, but I'm making that assumption just to be safe.
I'm not using any outputs that don't make a sound at all, or that make a sound that couldn't be made by my mouth (without getting too much into the weeds of what kind of volume output control my specific character would have as a warforged). Relatedly, I don't want any component of the earpiece to make any repetitive sounds unrelated to the intended output. V1.0 of this had a separate heart object with components that whispered tick sounds to count out minutes for the clock and define active/inactive states for the scanner and listener, but I realized there would be glitches if the heart and earpiece dropped communication with one another (by being in an antimagic field, or by being more than 30 feet apart). This version avoids that.

Again, this is implementation and not theory. In the context of an adventure, in which I don't have unlimited money, unlimited time, or unlimited access to resources, can I use MM to create something that would actually be useful for me and my party members? For that matter, something that is more useful than whatever else I could have reasonably used that time and money for? In this case, I feel like the benefits provided by the Traveler's Earpiece are probably good enough to justify the 13+ hours and 660+ gp, whereas spending weeks/months and thousands of gp on making a supercomputer would not be.

Spoiler: Maybe using phonemes only?

Show

If I did have a unique reference-frame-defining object, I guess I could consolidate things into the phonemes only. The output of the non-phoneme ones currently:

w ə n
t u
θ r i:
f ɔ: r
f aɪ v
s ɪ k s
s e v ɪ n
eɪ t
n aɪ n
t ɪ n
ə l e v ɪ n
t w e l v
oʊ
θ ɜ:ʳ t i: n
f ɪ f t i: n
t i: n
t w ɪ n t i:
θ ɜ:ʳ t i:
f ɔ: r t i:
f ɪ f t i:
oʊ - k l ɒ k
eɪ - ɪ m
p i: - ɪ m

The most common one is t with 12. I'm going to give 75 milliseconds per phoneme, but presumably in practice this would require some more finessed timings. Let's assume the earpiece also contains an internal component that is a metal disc with twelve inscribed arrows pointing outwards from the center and labeled 1-12. you could put the odds on one side of the disc and the evens on the other to save space. So, as a test, the magic mouth would be:

Whisper "t" if any of these three conditions are met:

These two numbers:

The number of milliseconds that have passed since the most recent instance of a creature speaking the words "current time" while holding this object
The number of minutes that had passed at the time of the above occurrence since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT"
have any of the following 7 properties:

The first number is 100 and the modulus of the second number and 720 is from 0 to 59 inclusive, 120 to 179 inclusive, or 600 to 659 inclusive.
The first number is 175 and the modulus of the second number and 720 is from 480 to 539 inclusive.
The first number is 800 and the modulus of the second number and 60 is 2, 10, 12, or from 20 to 29 inclusive.
The first number is 875 and the modulus of the second number and 60 is 8.
The first number is 950 and the modulus of the second number and 60 is 13 or from 30 to 39 inclusive.
The first number is 1025 and the modulus of the second number and 60 is 15 or from 40 to 59 inclusive.
The first number is 1100 and the modulus of the second number and 60 is from 20 to 29 inclusive.

Both of the following statements are true:

The number of seconds that have passed since the most recent occurrence of a creature speaking the words "start scanner" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball" has both of the following properties:

The number is less than the number of seconds since the most recent occurrence of a creature speaking the words "stop scanner" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
The number is less than the number of seconds since the last occurrence of this object not being carried by a creature that is also holding a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
This number:

The modulus of the number of milliseconds that have passed since the most recent instance of a creature speaking the words "start scanner" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball" and 6000
and these paths:

The paths from the center of the nearest metal disc inscribed with 12 arrows labeled with the numbers from 1-12 to the centers of mass of any creature in range that is not holding a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball"
have either of the following 2 sets of properties:

The number is 100, and at least one of the paths has the following property:

Of the 12 dot products taken between the path and the 12 directions indicated by the arrows inscribed on the nearest metal disc inscribed with 12 arrows that are labeled with the numbers 1-12, the greatest is the one corresponding to the arrow labeled with the number 2, 10, or 12.
The number is 175, and at least one of the paths has the following property:

Of the 12 dot products taken between the path and the 12 directions indicated by the arrows inscribed on the nearest metal disc inscribed with 12 arrows that are labeled with the numbers 1-12, the greatest is the one corresponding to the arrow labeled with the number 8.

Both of the following statements are true:

The number of seconds that have passed since the most recent occurrence of a creature speaking the words "start listener" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball" has both of the following properties:

The number is less than the number of seconds since the most recent occurrence of a creature speaking the words "stop listener" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
The number is less than the number of seconds since the last occurrence of this object not being carried by a creature that is also holding a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
A creature that is not carrying this object utters any intonation of the "t" phoneme at a volume less than 45 decibels.

That takes me a little over 5 minutes to read aloud at an understandable pace, so I guess it fits my rules.

**Willowhelm** · 2022-05-16, 10:25 PM (ISO 8601)

I'd love to see an attempted implementation of that!

Unfortunately your limitations would make this impossible. Not allowing variables or memory and requiring the entire "condition" to be spoken allowed within a set time frame makes the single casting "final form" essentially impossible.

I'll happily take another look through this but can you clarify some stuff for me?

Your OP says

This object should solve three main problems that come up frequently in the campaign: nobody ever knows what time it is, creatures keep sneaking up on us, and we don't have an easy way to communicate without being overheard.

Is there any reason why a clock (or someone with the keen mind feat), a weapon of warning, and some manner of telepathy (class, race, magic item, spell) are not available options? Given you intent to speak into the whisper repeater it seems like message would do the job just fine (or is this intended for eavesdropping?)

I'm asking because this is what i meant by replacing magic objects. Some of these things exist and their mechanical benefits are (in theory) "balanced" by their rarity and price. By using MM to effectively replace them (and at a low level) you warp the balance of the game a little.

You might also enjoy reading this write up of magic mouth through the editions (and the links from there).

Another quick one is the internal variables decision you've made.

No defining internal variables, including ones to remember specific states. Assume the trigger is being "read" by the spell each time, with no memory of prior readings of the trigger. The only things it "remembers" are audible or visual conditions.

How do you square this rule with conditions like this:

The number of seconds that have passed since the most recent occurrence of a creature speaking the words "start scanner" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball" has all of the following properties:
The number is an integer multiple of 6.
The number is less than the number of seconds since the most recent occurrence of a creature speaking the words "stop scanner" while holding both this object and a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
The number is less than the number of seconds since the last occurrence of this object not being carried by a creature that is also holding a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".

This repeatedly refers to "the number". To me that is a "variable" being used in the conditions. It refers to a count used elsewhere, to avoid duplication of the entire text of what that number is. Can you clarify what is and isn't acceptable?

It's also an example of state being stored - the number of seconds since the last time something was said is not an instantaneously available piece of information at the time of the trigger. It is something that the MM is constantly "remembering" from the moment of casting forwards.

As such it seems like you are already relying on abilities you say are restricted, both in the casting speech and in the implemented trigger.

If you treat MM as a rigid set of rules and capabilities then you have a double edged sword. Everything you say it can do opens up many more possibilities than you expect. Everything you say it cannot do shuts down more than you expect. As soon as you realise that you have to be flexible and "reasonable"... all the precise wording and limitations you put in place kind of evaporate. The only thing that matters is what the DM agrees it is capable of, not your prowess in crafting complex conditions.

**Baphomet** · 2022-05-17, 12:43 AM (ISO 8601)

Originally Posted by Willowhelm

Is there any reason why a clock (or someone with the keen mind feat), a weapon of warning, and some manner of telepathy (class, race, magic item, spell) are not available options?

This just...isn't the game where that's the thing we all prioritized for our characters? We haven't seen any clocks or weapons of warning at any point. I don't think the former has been invented. Everyone needs their ASIs for other things and can't fit the Keen Mind feat in. We actually do have a Kalashtar and a Ghostwise halfling, but the DM is strict about only allowing them to talk to one person at a time telepathically and we run into frequent problems where using the action to connect to another creature is a suboptimal use of time. The only magic users in the party are the Kalashtar Bard and me, the Warforged Artificer, and we can only learn so many cantrips.

Originally Posted by Willowhelm

I'm asking because this is what i meant by replacing magic objects. Some of these things exist and their mechanical benefits are (in theory) "balanced" by their rarity and price.

I think the main disagreement here is that, if I can show that these things are possible with this spell, then it is just another way to access those functions. Some options are better than others. If I said "The levitate spell should solve a problem that comes up frequently in my campaign: there are a lot of walls that are too tall to jump over," you wouldn't say that I'm replacing the Spider Climb spell because it's also balanced at the same level. Yes, Spider Climb can last longer and doesn't have a weight restriction, but Levitate is more versatile and is usually the one I'd pick if I needed one or the other. There are pros and cons to making this object versus buying any of the objects or taking any of the feats or spells you listed, and one of them is going to be a better choice, and it's not always going to be the earpiece in every situation.

Originally Posted by Willowhelm

This repeatedly refers to "the number". To me that is a "variable" being used in the conditions.

It might qualify as a variable, but it's being set in the course of the instruction, in the same way that "a silver bell rings" could be said to define a bell that is made of silver and a ringing sound. I'm defining it in terms of audible or visual conditions, not prior computations.

To put it in programming terms, I'm treating the trigger like a function that's being called repeatedly in a loop. The only argument the function accepts is a comprehensive list of all audible and visual conditions that have occurred in 30 feet of the spell since it was cast. I'm assuming that this argument includes some concept of timing, like time stamps associated with each condition, because I don't think the average DM would disagree to a trigger like "a silver bell rang 15 seconds ago" and that wouldn't be possible if the spell didn't understand time. You might instantiate local variables inside the function during the process of computing its output, but they're more like computational (or, in this case, semantic) shortcuts than actual state memory. They're deleted when the function call is over and the function will have no idea what they were when it is called next time.

I do think you could make binary memory systems since MM creates an audible and visual condition when it's triggered. You'd just need an unambiguous way for other MMs to refer to the objects with the MMs that encode the memory, but that's easily done by inscribing the objects with some unique text or symbol. Version 1.0 of this earpiece used this to encode the state of the functions that you can toggle by having components on a separate object act as repeaters that start when you toggle the functions on and stop when you toggle them off. I removed them to fix glitches and reduce the total number of MMs required, at the expense of making the other MMs have more complex triggers.

EDIT: to clarify again, this thread is about implementation more than theory. I would sum up my intent here as "Here's a set of rules MM might follow. I've tried to keep them reasonable enough that a good deal of DMs might agree with them. If your DM does agree to them, here's how you could use this to create a useful object." Other threads on this subject have implied that this sort of thing might be possible but then just left the actual assembly manual as an exercise for the reader. The ideal situation I'm trying to facilitate here is: you show your DM these rules about what the spell can do, your DM says they agree to them, you point them to this thread and say "I'm building this now," and they read it and say "Okay, that makes sense, pay the time and the material costs, you now have this object." I am not suggesting that you bog down your next session spending an hour reading pages and pages of "under this condition, if these objects defined this way have these properties, compare this number to blah blah blah," and then expecting the DM to A) stay awake long enough to listen to the whole thing and B) have the amazing mental capacity to parse what the thing is going to do in practice while it's being verbally shotgunned at them. I do want to be thorough enough that, if your DM happens to be a programmer, they're not going to read this thread, find a glitch in my wording, and spring some sort of unexpected consequence on you in the game later.

I'm absolutely down to discuss what should be reasonable limitations for the spell! This stuff is fascinating as a thought experiment! You can absolutely change my mind on some of my assumptions! That might make me change how the earpiece works. I'd also be happy to hear other things it could reasonably do that add more value than what they cost, or ways to optimize the number of actual MM spells that need to be cast without limiting what it can do.

**Willowhelm** · 2022-05-17, 08:21 AM (ISO 8601)

Thanks for the clarifications. There’s no disagreement from me, I’m just trying to understand the whole situation to better tailor my responses.

For what it’s worth: I play, I DM, my degree is engineering with computer science and my day job is designing, building and testing software and cloud infrastructure. It strongly affects my approach to this whole topic and my use of terms.

I’ll take another look when I get a chance.

**Baphomet** · 2022-05-17, 04:59 PM (ISO 8601)

Originally Posted by Willowhelm

Thanks for the clarifications. There’s no disagreement from me, I’m just trying to understand the whole situation to better tailor my responses.

And thank you for getting the clarification and giving your input! You definitely helped me realize that I needed to call out my intent for this thread more clearly from the beginning. It's less about saying "here's what's possible" and more about saying "here's a set of assumptions about what's possible, and here's a concrete example of what you can do with that." I've edited the first post again to be more conducive to that understanding of my purpose here.

EDIT: You also helped me realize that I was basically defining local variables in the triggers already, so I went ahead and reworded a lot of them to make that more explicit. It's now slightly wordier (it grew into the second post) but I think all of the triggers are a lot easier to parse now. It also fixed something that bugged me: there were times when it would ask for the time since a triggering event that might not have actually occurred yet. In all of those cases the intention was that the spell wasn't triggered, but it still irked the programmer in me that there were potential NaNs being thrown around. I don't know if magic can segfault but I think I dealt with all of those situations just in case.

**Willowhelm** · 2022-05-17, 10:52 PM (ISO 8601)

These notes were from a version before your edits so they might no longer be relevant. I will try and take another look. Really this should be a git pull request for proper revision tracking ;P

Is the listener intended to relay stuff between team members or is it intended for bugging a room (or both!)?
Many conditions reference carrying the item when i believe it is intended to be worn.
I think the listener functionality can be removed to its own object as the only real overlap is the “oh” sound (unless you go with the plan to use phonemes for clock output)
(I misunderstood the listener function before - now i get it.) You’ll get crosstalk and also (potentially, based on pedantry) an infinite loop on the condition. “A creature that is not carrying this object utters any intonation of the "b" phoneme at a volume less than 45 decibels.” . The mouth needs to wait until after ‘b’ has been said (to recognise that it is that phoneme), at which point the conditions continue to be met forever. It’s the difference between “a bell is ringing” and “a bell has been rung”. This is entirely an issue of treating the spoken text as logic vs intent of the caster (which is again just a DM discussion on how you want this to work out - i’d ignore it and have it work in the intended manner either way)
You may also get some “speech” from creatures you don’t intend. If a dog makes a “wuh” as part of its bark, do you want to repeat that?
I’d set at midday instead of midnight. More user friendly and easier to calibrate with a sundial etc.
Sew the pouch around the outside of the taco + wire - more comfortable and doubles up as tension - no need for the additional strips.
I’d make the beads out of something other than metal - just lighter and easier to work with.
putting the grains into wax is going to affect their ability to make audible sound. The mouth repeats at the same volume and you’ve set that at 40dB max and then wrapped them in wax. Arranged on a tiny strip of glue would work, you also may need to have faces on them in order to make sure the mouth appears on the outward-facing part (Depends on ruling, but you ruled that the grains were too small for faces so this may affect component size). I’d just leave them loose inside a very thin enclosure.
I’d use minutes and hours instead of seconds modulo x with remainder y. Just say “1 hour after last reset and every 12 hours after that” (or whatever).
Your bead orientation only works for the horizontal plane. Creatures above/below will be confusing on the scanner. (I'm picturing the aliens scene where "they're right on top of us!" and you can't see them.)
Also what happens when the user lies down? You also specify that the sweep is in the horizontal plane, but if the bead rod is oriented horizontally (lying down) then multiple beads would trigger on the "horizontal plane"
I’d consider orienting off the user’s body/head instead.
How are your beads (which are fully enclosed) “seeing” the creatures they’re sensing? Is this all audio triggers? If so how is it judging size? I may have miss-read the bead location but even if they're not fully enclosed they are blocked by your head for a substantial amount.
I’d make additional activation conditions that are not spoken. Eg tapping the earpiece once with an index finger for the time. You may not always want to have a verbal component to use the functionality, especially the scanner.
This seems problematic:
‘The number is less than the number of seconds since the last occurrence of this object not being carried by a creature that is also holding a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball”.’
- If the earring is being worn this is always true. It also deactivates the scanner if you try and pass it to someone. I assume the latter is intentional but i'm not sure why?
It would make it less user friendly but to reduce complexity the time could be read simply as the digits. 1-2-3-0 instead of 12 30. . No need for the teen, o’clock, edge cases etc. If you drop the phonemes and whisper functionality you can make a budget version with 10 castings instead of 66(?) You could also go with 24 hour time to skip the am/pm casting. I’d personally go with am/pm or skip it entirely.
I’d also consider making a physical clock with an arcane lock + single magic mouth as the escapement. If you’re not going for the complexity of a modern clock this is actually very simple to achieve. It would cut down on costs even further but it would remove the output for the scanner.
I’d be inclined to make this whole thing a hand-held object with visual output instead of an earpiece but i understand thats not the original intent.
The speech will “flow” better if your conditions trigger from the end of the other magic mouths instead of at precise time intervals. Harder to specify but a nicer result.
Your scanner functionality could be replaced with one casting that just does a buzz/beep for anything in range, then a second one which says "hotter" when you move your arm closer to pointing at the creature. Again - this isn't going to make the item you described but it is significantly cheaper and simpler and requires fewer assumptions about what the MM is capable of.
the scanner uses the security key to recognise safe people - but does it have to be visible at all times? That's going to break your security because if it's always out people will see this bizarre image and put 2 and 2 together sooner or later.

I'm glad you've seen the conditions already had a form of variables. I think you can simplify the text further to make it more human readable.

Having spoken words trigger things demonstrates modes and state are possible within your rules. I know that this is something i’ve communicated poorly in earlier posts but:
‘To activate this feature, speak the words "start scanner”’ shows that there is an on/off mode with different behaviour in each state. Similarly the clock has silent vs talking and the listener can be activated too. The magic mouth maintains a history of things that have happened before the current time.

You’re achieving it by checking the time from two different phrases were said but that can be done for many other kinds of states. Like… Beep when "the number of people that have opened this door is the same as the number of fingers i hold up". You’ve already ruled the magic mouth can count, do integer math, modulo, less than, greater than etc etc. This should be legal by your rules i think? And it shows that the magic mouth can “store” a count of an event occurring. That event itself can be a whole other complex condition.

Edit: I see that the rules updates specify some more of the limits and directly apply to some of my comments here. I still think the ignore list is functionality you’ve already approved, but I’ll drop it as unwanted. I’ve left it here just in case

I *think* by your rules you can add people to the ignore list with a clause in the condition like:
" least one creature that is larger than tiny size and is not on the ignore list is located in a space inside a horizontal cylindrical sweep from -15 to 15 degrees of the direction this object is facing." and "a creature is on the ignore list if the number of seconds since I lastpointed at them and said 'ignore this creature'" is not 0 and more than the number of seconds since I said “stop ignoring all creatures” (and blah blah blah extra conditions). From a MM ruling point of view i think this is justified by your other points and from a DM point of view i think it is a simple feature to avoid bogging down the game and i would allow it without question (assuming i'm already signing off on giving you a creature scanner)

Edit: I also see the updated rules call out that you’re not interested in this for this topic. I still recommend the stuff below purely for academic interest but I’ll drop the subject for the purpose of this thread.

I highly recommend playing around with https://www.nandgame.com/. In the arcane programmer thread there was talk about making individual MM into logic gates and how that could result in a computer. That's correct but fails to grasp that one casting can be an arbitrarily large number of logic gates, assembled in a way we choose. Once it is agreed that an MM has functionality of the most basic logic gate (which is undeniable)... so much else is possible. Assuming a clock pulse (which you have already granted) you can get all the way up to making a latch. If you agree that the condition can have self-referential clauses (variables) then you can make latches in the same MM as the rest and then you're really off to the races because you can make memory, ram and everything required for a full computer... In one casting. But i digress.

**strangebloke** · 2022-05-17, 11:15 PM (ISO 8601)

what even is this thread?

...Nothing much to contribute, just saying this is appreciated.

**Baphomet** · 2022-05-18, 03:34 PM (ISO 8601)

Numbering your list to make it easier to track my answers-

Originally Posted by Willowhelm

Is the listener intended to relay stuff between team members or is it intended for bugging a room (or both!)?
Many conditions reference carrying the item when i believe it is intended to be worn.
I think the listener functionality can be removed to its own object as the only real overlap is the “oh” sound (unless you go with the plan to use phonemes for clock output)
(I misunderstood the listener function before - now i get it.) You’ll get crosstalk and also (potentially, based on pedantry) an infinite loop on the condition. “A creature that is not carrying this object utters any intonation of the "b" phoneme at a volume less than 45 decibels.” . The mouth needs to wait until after ‘b’ has been said (to recognise that it is that phoneme), at which point the conditions continue to be met forever. It’s the difference between “a bell is ringing” and “a bell has been rung”. This is entirely an issue of treating the spoken text as logic vs intent of the caster (which is again just a DM discussion on how you want this to work out - i’d ignore it and have it work in the intended manner either way)
You may also get some “speech” from creatures you don’t intend. If a dog makes a “wuh” as part of its bark, do you want to repeat that?
I’d set at midday instead of midnight. More user friendly and easier to calibrate with a sundial etc.
Sew the pouch around the outside of the taco + wire - more comfortable and doubles up as tension - no need for the additional strips.
I’d make the beads out of something other than metal - just lighter and easier to work with.
putting the grains into wax is going to affect their ability to make audible sound. The mouth repeats at the same volume and you’ve set that at 40dB max and then wrapped them in wax. Arranged on a tiny strip of glue would work, you also may need to have faces on them in order to make sure the mouth appears on the outward-facing part (Depends on ruling, but you ruled that the grains were too small for faces so this may affect component size). I’d just leave them loose inside a very thin enclosure.
I’d use minutes and hours instead of seconds modulo x with remainder y. Just say “1 hour after last reset and every 12 hours after that” (or whatever).
Your bead orientation only works for the horizontal plane. Creatures above/below will be confusing on the scanner. (I'm picturing the aliens scene where "they're right on top of us!" and you can't see them.)
Also what happens when the user lies down? You also specify that the sweep is in the horizontal plane, but if the bead rod is oriented horizontally (lying down) then multiple beads would trigger on the "horizontal plane"
I’d consider orienting off the user’s body/head instead.
How are your beads (which are fully enclosed) “seeing” the creatures they’re sensing? Is this all audio triggers? If so how is it judging size? I may have miss-read the bead location but even if they're not fully enclosed they are blocked by your head for a substantial amount.
I’d make additional activation conditions that are not spoken. Eg tapping the earpiece once with an index finger for the time. You may not always want to have a verbal component to use the functionality, especially the scanner.
This seems problematic:
‘The number is less than the number of seconds since the last occurrence of this object not being carried by a creature that is also holding a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball”.’
- If the earring is being worn this is always true. It also deactivates the scanner if you try and pass it to someone. I assume the latter is intentional but i'm not sure why?
It would make it less user friendly but to reduce complexity the time could be read simply as the digits. 1-2-3-0 instead of 12 30. . No need for the teen, o’clock, edge cases etc. If you drop the phonemes and whisper functionality you can make a budget version with 10 castings instead of 66(?) You could also go with 24 hour time to skip the am/pm casting. I’d personally go with am/pm or skip it entirely.
I’d also consider making a physical clock with an arcane lock + single magic mouth as the escapement. If you’re not going for the complexity of a modern clock this is actually very simple to achieve. It would cut down on costs even further but it would remove the output for the scanner.
I’d be inclined to make this whole thing a hand-held object with visual output instead of an earpiece but i understand thats not the original intent.
The speech will “flow” better if your conditions trigger from the end of the other magic mouths instead of at precise time intervals. Harder to specify but a nicer result.
Your scanner functionality could be replaced with one casting that just does a buzz/beep for anything in range, then a second one which says "hotter" when you move your arm closer to pointing at the creature. Again - this isn't going to make the item you described but it is significantly cheaper and simpler and requires fewer assumptions about what the MM is capable of.
the scanner uses the security key to recognise safe people - but does it have to be visible at all times? That's going to break your security because if it's always out people will see this bizarre image and put 2 and 2 together sooner or later.

The main intent is to allow conversations between teammates. I could easily restrict it to that, but I thought the ability to listen in on nearby whispered conversations between other people was a nice added bonus.
Good point. I was trying to use "carry" to encapsulate all states where an item is in someone's possession, including wearing it. Now that you mention it though, I know there are lots of spells that use the phrase "carried or worn." I'll make the wording reflect this to avoid ambiguity.
I could move the listener to its own object, but why would I? It's an important problem to solve and I'm already making an earpiece. That said, I am considering using the phoneme sounds for the clock/scanner output. I realize now that it's easy to overcome my previous objection about developing reference frames on the objects that actually have MM cast on them because I can just have them all unambiguously refer to a separate reference-frame-defining component anyway. In fact, the separate direction-defining object solution is probably more elegant and simpler than the current one. I could use that to solve another problem that currently bugs me about the scanner: if there are multiple creatures in range at once, it's going to say all of the numbers for the directions to them at the same time, then "o'clock". If all of the components that speak those numbers have access to all of the 12 directions that the others are using then I can make them recite each number in a list.
Excellent catch. Where the loop is concerned, I think the new version should patch this bug; it only repeats a spoken phoneme if it has been spoken since the last time the MM spell activated (or since the listener was activated, if that hasn't happened yet). I'm not sure what to do about crosstalk. Maybe I can have separate "listen only to teammates" and "listen to everyone" functions?
You're right, that is ambiguous. Is there a way to phrase it to make it only respond to speech and not other sounds? I can't really think of one that doesn't rely on checking to see if the sound is part of a word, in which case the listener doesn't know if the condition is met until after the word is finished, at which point all the phonemes in the word would go off at once. The more I think about it the more I think that restricting the listener to speech by approved creatures is the better way to go.
Now that you mention it, that makes a lot more sense. I'll change that in the next revision.
That could work too. My reasoning at the time was that I wanted the pouch to be small and self-contained just so it's harder for sand grains to start leaking out if you go someplace hot.
I considered this. Internal reasoning was "my character personally has smith's tool and leatherworking tool proficiencies so I'll use those things", but that's not really a good reason. I suppose all of the rigid parts could be made out of metal or wood or glass, depending on what kind of materials and tools you have access to.
The spoken message doesn't have to be at 40 decibels or less, only the triggering circumstance (Although the new version just says "whisper" instead of setting the 40 decibel limit since I think "ability to recognize a whispered sound" is a reasonable assumption based on "ability to recognize a ringing sound"). Also, sound doesn't have to be very loud to hear when it originates right by your ear. I don't think it's too unreasonable to think I could make that work.
Also a good point. On the one hand, I'm driven to be specific because I don't want any unintended consequences. On the other hand, I'm allowed to be general because the spell can literally parse abstract descriptive concepts written in prose. I'm having trouble deciding when to nail everything down and when to trust the spell to do its thing. I'm sure there are many better ways to word this and I'll probably keep improving it over the successive iterations.
True. Another argument in favor of the "comparing dot products with direction arrows inscribed on a clock face attached to the earpiece" method I used in my example in a reply a little ways up. That does away with all the bead nonsense and it's trivial to include an "up" condition too.
Ditto.
Or that. I was avoiding it to dodge ambiguity when more than one creature is carrying the object but that's probably such an edge case that it's fine if behavior is weird in that circumstance. The disc thing might still be more elegant though, since it removes the need for the spell to understand the concept of degrees.
One of the necessary assumptions is that the spell isn't obstructed by solid objects; at the very least it needs the "can penetrate most barriers, but it is blocked by 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt." clause. Otherwise, even if the components are outside the earpiece, if you wear it on your left ear it's going to fail to detect anything on your right because your head's in the way.
True. I'll work that in.
If you're captured and someone takes all your stuff while either of the "secret" functions are active, I don't want your captors to be able to use those functions. Might not come up, but it was an easy add so I added it.
Hmm. In retrospect, I don't know why I thought the "o'clock" and "AM"/"PM" was important enough to spend another 30 GP and 33 minutes on. 24 hour time is a fine alternative. I think single digits are problematic where the creature scanner is concerned though, especially if I plan to add listing functionality. Is "one two" one creature at 12:00 or is it a creature at 1:00 and another at 2:00? As for the "budget" version, a good middle ground would be to still speak numbers. I'd have 1-13, 15, "teen", 20, 30, 40, and 50. I could even omit the "oh", since "twelve eight" is still unambiguous. That's 19 spells, or 20 if I add "up" to the creature detector. The whisper listener was also the only function that needs to be discreet, so I could do away with the whole whispering earpiece thing and just make like a pocketwatch or something. Turn on the scanner and set it in the middle of camp while the meatbags are unconscious.
Is there an Arcane Lock implementation that gets you the clock in a visual form for less money than the spoken one? Each Arcane Lock requires 25 gp of spell components. How do you control multiple ALs with one MM?
ditto.
Seems like a sensible alternative to developing timing cues, but might get too wordy. I'll see what I can come up with.
Maaaaybe. I could see many DMs ruling that the amount of time it takes to point around until you find the right direction is prohibitively long, though. If I just want the creature detector I could probably pare it down to forward/backward/left/right/up. 5 is more expensive than 2 but 55 gp is still a fairly trivial expense.
I'm still assuming that the spell's detection abilities aren't obstructed by something like a pocket or a backpack, which is where the key would presumably be kept.

Originally Posted by Willowhelm

‘To activate this feature, speak the words "start scanner”’ shows that there is an on/off mode with different behaviour in each state. Similarly the clock has silent vs talking and the listener can be activated too. The magic mouth maintains a history of things that have happened before the current time.

You know, I've come around on this. Even if the spell isn't internally allowed to "remember" decisions made in prior trigger attempts, all of those decisions were based on visual or audible conditions and we're operating under the assumption that it has a record of those. The spell can explicitly parse language as ambiguous as "a silver bell rings." If the spell truly can't use memory of decisions outside the scope of any individual trigger check, and I included something like, "The scanner is activated when the creature wearing this object speaks the phrase 'start scanner'. The scanner is deactivated when that creature speaks the phrase 'stop scanner' or ceases to wear this object. If the scanner is active..." the spell could probably parse it anyway. It could reasonably do something like check whether the most recent event that could activate it is more recent than the most recent event that could deactivate it without me explicitly spelling out how to do so. Of all the reasons that a DM might disallow the Traveler's Earpiece, "it defines too many global variables" would probably not be in the top 10. I'm taking that rule out.

Originally Posted by Willowhelm

"a creature is on the ignore list if the number of seconds since I lastpointed at them and said 'ignore this creature'" is not 0 and more than the number of seconds since I said “stop ignoring all creatures” (and blah blah blah extra conditions).

The only thing that has me iffy on this one is how the spell knows whether any given creature is the one I pointed to. Is it based on how a creature looks and sounds? How robust is the list of features that it checks? Is it so general that it gives a false positive in the presence of any creature of the same race with the same skin and hair color? Is it so specific that it gives a false negative when the creature gets a new bruise or cut? Maybe it bases it on the creature providing an unbroken chain of visual or audible circumstances that it can detect since the creature was added to the ignore list, but if that's the case does it lose track of them when they leave the spell's 30-ft range? Am I being too pedantic again by asking these questions in the first place? Maybe I should trust the spell's common sense at identifying creatures when given a detectable real-life sample of that creature's appearance. I guess that can be a reasonable guideline, but I'll have to think about what that might imply.

**Willowhelm** · 2022-05-18, 05:50 PM (ISO 8601)

I think the tool proficiency you want for this is jewellers tools.

I think you underestimate the wax’s dampening abilities. An earplug will block out that level of sound and you’re basically wrapping them in a wax earplug. I'd go with larger, inexpensive objects that you can constrain without the wax. Tiny beads on a thread works. Or just a bunch of threads in fact.

I think your orientation is another thing that, as a DM, i would hand wave. It’s clearly within the abilities of the spell but just a PITA to specify so i’d just say it works as intended. If you want to write out clear cut conditions then go for it. I'd base it off something like axes aligned with the user's head or chest, or an item like a hat/circlet/hairpin so they can adjust it separately.

Your assumption that the mouth essentially has superman style X-ray vision seems like a big stretch to me! Id be much happier to agree that you could automatically recognise specific creatures (the PCs) than say the MM can see through backpacks and heads etc. That gives you an MM which can auto-spot all sorts of secret doors, traps, hidden creatures etc etc…

So i immediately thought why not mount the beads on your head (directly in hair, on a hat band, circlet.. whatever) and that made me realise you can skip all the directions-via-clock-time and just have the beads beep in scanner mode. Your PC's ears are going to judge which bead is beeping (and it's direction) much more quickly than I'd recognise an hour and translate it to a real-world direction. I now have an image of the classic Australian hat with corks hanging off, which start talking when something approaches.

But again... that's not the earpiece you're designing. Sorry!

For deactivating when taken I’d just say that…. part of the condition is “Will not trigger unless worn/carried by me”

Your response to 17 explains why i said 3 - As the functionality of the listener is quite distinct from the clock and scanner, decoupling them simplifies both. My character used MM to replace/extend the alarm spell. Instead of ritual casting alarm over and over he just had two sets of MM objects to place on a perimeter and they triggered the “buzzer” MM in the “quiet” set, or just yelled at full volume in the loud set. Depending on the way you rule alarm and MM.. there are pros and cons to both. (Eg can alarm or MM be set to ignore mice coming into camp? either? Both?)

For the arcane lock clock I was not imagining an entire clock using arcane locks for display. Essentially you’d build a normal mechanical clock/watch but the quality of the time keeping can be a little more slap-dash because an arcane lock (triggered by the MM speaking the password at a prescribed rate) will only unlock for exactly 1 minute. You can thus have a mechanism which would run fast normally, but is limited by the lock. You still require too much other clockwork technology to make this work as you said that clockwork doesn’t really exist in this campaign. (IF you rule that the mouth actually moves and is not just illusory, then you can eliminate all the hard parts of a clock’s internals and it is very easy to make a clock without any arcane lock or clockwork technology)

A visual-output clock face could use a similar amount of MM as the speaking version. You would have mouths painted with a different colour inside the mouth. When it opens, you see the internal colour. When it is shut, you do not. Lets say you have a clock face with the numbers 1 to 12 around it as normal. You can spend a lot and get minute and second “hands” that constantly display a digital clock face, or you can just have it pulse next to the number for the hour and then the minute when triggered. Or you can make 8 segment displays… Start with a cheap option and spend your treasure on upgrades as you go :P

I agree there’s a middle ground between the super-budget scanner option i presented and the fine-grain possibilities. I was just demonstrating that a different approach can work without requiring complex condition text. I’d have thought either just the buzz would be enough, or the creature is hiding so you’d have time for the pointing. If they’re charging in and attacking… your scanner isn’t going to get you any real benefit because most creatures can close the distance (30ft) and attack in one round - so your own voice calmly telling you “12 o’clock” as the orc smashes you in the face…

Careful with accepting what you’re terming global variables… With an arbitrary number of global variables you have volatile memory and you’re edging closer to having a full computer! :P (I think you’ve actually already accepted enough)

I can see the issue with the limitations of recognising the same characters. I think that this is well within the “acceptable” capabilities of the spell but… your rules! If you want it to be bullet proof then it can absolutely forget them once they’re out of range but you can re-add them before setting up camp every night. Again, As DM i’d just accept it because it’s pointless book-keeping (to me). You can also just give people a password instead(which again could be stored/changed via keywords so you’re not stuck with one permanently) and give the MM a condition where the creature needs to speak that word within a time frame after entering range.

The link i provided earlier (with MM through the editions) shows that the spell used to be utterly bonkers broken. Detecting alignments and ages etc in the examples given. I don’t think recognising a creature as the same creature it has seen before is game-breaking. (Of course… other things about magic mouth’s insane AI-classifier abilities could be. It knows what a bell is. It knows what a creature is (vs non-creatures). Is silver a colour? A metal? Can it detect precious metals?! Can it detect food? And once again I go down a rabbit hole of irrelevant MM rules instead of focusing on your use case….)

**Miele** · 2022-05-19, 01:32 PM (ISO 8601)

I wouldn't allow this, based on a simple reason: if you can, anyone else with the spell and gold, can do it as well.
Suddenly infiltrating places where powerful people reside is impossible, hiding becomes pointless, magic items become obsolete, etc.
You open a giant can of rotten worms. The main reason tho is that it goes well beyond the intended use of the spell.

**Willowhelm** · 2022-05-19, 02:38 PM (ISO 8601)

Originally Posted by Miele

I wouldn't allow this, based on a simple reason: if you can, anyone else with the spell and gold, can do it as well.
Suddenly infiltrating places where powerful people reside is impossible, hiding becomes pointless, magic items become obsolete, etc.
You open a giant can of rotten worms. The main reason tho is that it goes well beyond the intended use of the spell.

I get this, and i'd accept it at your table, but (i think) it is clear this is all only with DM blessing anyway.

What are you referring to as "this" though? The earpiece? One of the abilities Baphomet believes the spell has? Or the entire endeavour of using the spell in a novel way?

NB. At my table the (accidental) x-ray vision aspect would absolutely not work. Too OP and in my opinion not in the spell description. I would rework the conditions and design to avoid that requirement but maintain the same functionality otherwise.

I don't want to derail too much but what aspect of replacing a clock, the alarm spell, or the message cantrip seems so OP? That's what this thread is designing/critiquing. (My tangents about the theoretical implications non-withstanding).

Powerful people can already do all these things. (Lvl 1 adventurers can too. Resourceless.) In my understanding, MM was always more of a DM dungeon-building spell anyway which is why its historic versions have such broken abilities.

I've also pointed out (i know... it's a big wall of text back there) that the creature scanning is actually going to be totally useless in most situations. The range is such that the enemy will be stabbing you before your earpiece even speaks.

**OvisCaedo** · 2022-05-19, 02:53 PM (ISO 8601)

The message cantrip is kind of awful as written in 5e, so chances are anything that 'replicates' it will actually be WAY better. Not that I have a particular issue with that concept. The "send a subtle message" spell being "audibly say verbal components while waving your hands around every six seconds and frantically whispering your messages in the gaps between" is... silly. I don't think the implications of its components+duration were thought out when the cantrip was written.

**Willowhelm** · 2022-05-19, 11:14 PM (ISO 8601)

I've tried rewriting your first bead condition a little. ~~I dropped the scanner functionality as this is more of a demonstration than an attempt to duplicate the exact functionality.~~

I think writing the conditions in this way has a few benefits. Making it easier to read will get your more feedback compared to the giant wall of text, and it will be easier for your DM to see that you're not trying anything sneaky.

Message spoken during casting:
“one” (whispered)
Condition:
Someone wearing or carrying this object says “Time please?” and the time since that person said “clock set” is between 1 and 2 hours previous (or the same period plus a multiple of 12 hours), or 1, 21, 31, 41 or 51 minutes (rounded down) more than any number of hours (but after a slight delay)
OR
Every 6 seconds, if they have not said “scanner off” since they said “scanner on” and a creature larger than tiny is present unless they have also said “ignore this creature” while pointing at that creature since the last time they said “reset ignore list”

To me, that is much easier to read than:

Whisper "one" if any of the following 3 conditions are met, using the 5 definitions below them.
The 3 conditions:
1. clockCallEvent is not undefined, and clockCallEvent occurred exactly 0.1 seconds ago, and the modulus of minuteCount and 720 is from 60 to 119 inclusive
2. clockCallEvent is not undefined, and clockCallEvent occurred exactly 1.3 seconds ago, and the modulus of minuteCount and 60 is 1, 21, 31, 41, or 51.
3. All 5 of the following statements are true:
1. scannerStartTime is not undefined.
2. scannerStartTime is an integer multiple of 6000.
3. scannerStopTime is undefined or scannerStartTime is less than scannerStopTime.
4. scannerStartTime is less than the number of milliseconds since the last occurrence of this object not being carried by a creature that is also holding a securityKey.
5. At least one creature that is larger than tiny size and is not carrying a securityKey is located in a space inside a horizontal cylindrical sweep from -15 to 15 degrees of the direction this object is facing.
The 5 definitions:
1. "clockCallEvent" is an event defined as the most recent occurrence of a creature speaking the words "current time" while holding this object, if any. It is undefined if this has not occurred.
2. "minuteCount" is a number. If clockCallEvent is undefined, minuteCount is 0. Otherwise, minuteCount is defined as the number of minutes that had passed at clockCallEvent since the most recent instance of a creature speaking the words "set clock midnight" while carrying this object and also pressing a finger to a drawn depiction of an hourglass labeled "SET CLOCK MIDNIGHT".
3. "securityKey" is a type of physical object defined as a scrap of parchment bearing an ink drawing of a seven-legged spider struggling to swim in water above the open-mouthed head of a large snake which is labeled "candleball".
4. "scannerStartTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "start scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.
5. "scannerStopTime" is a number defined as the number of milliseconds that have passed since the most recent occurrence of a creature speaking the words "stop scanner" while holding both this object and a securityKey. It is undefined if this has not occurred.

If you drop the "x-ray vision" it also solves your directional issues. Simple put "blinkers" (like a horse's) around the bead and it will limit its vision to that scope. Physical design simplifies the condition immensely.

**Miele** · 2022-05-20, 06:02 AM (ISO 8601)

Originally Posted by Willowhelm

I get this, and i'd accept it at your table, but (i think) it is clear this is all only with DM blessing anyway.

What are you referring to as "this" though? The earpiece? One of the abilities Baphomet believes the spell has? Or the entire endeavour of using the spell in a novel way?

My reasoning is that a 2nd level spell, which has probably an intended use as warning against infiltrators or thieves and can already be used in some creative way, gets bumped up to monstrous level of power. You're building a modern 21st century portable radio (short range, yes) with an inbuilt stealth detector and cronometrical precision clock.
I'd accept the clock, probably, not the radar nor the radio. In the end it's a matter of balance.

We live in this era where technology has done huge leaps and we have access to the theory of how things work. Combine this with magic substituting for electronic chips and computations and I'm sure that with enough work and creativity and some DM leniency you could build a medium range missile loaded with delayed blast fireballs and nuke enemies from afar. How much is too much?

**JackPhoenix** · 2022-05-20, 06:05 AM (ISO 8601)

As far as I'm concerned....
- the object has to be big enough to form the mouth, which is a copy of the caster's mouth. No grains of sand or similar nonsense.
- MM has no Perception. It can react to visible and audible triggers, but it can't see anything behing heavy concealment, hear nothing clearly audible from its position and it can't notice any sneaking creatures.
- It can reacto to visible and audible triggers, but nothing else. Not the passage of time, not creature types, and not any extra conditions.

**Willowhelm** · 2022-05-20, 08:46 AM (ISO 8601)

Originally Posted by Miele

My reasoning is that a 2nd level spell, which has probably an intended use as warning against infiltrators or thieves and can already be used in some creative way, gets bumped up to monstrous level of power. You're building a modern 21st century portable radio (short range, yes) with an inbuilt stealth detector and cronometrical precision clock.
I'd accept the clock, probably, not the radar nor the radio. In the end it's a matter of balance.

We live in this era where technology has done huge leaps and we have access to the theory of how things work. Combine this with magic substituting for electronic chips and computations and I'm sure that with enough work and creativity and some DM leniency you could build a medium range missile loaded with delayed blast fireballs and nuke enemies from afar. How much is too much?

Your world, your rules. I’m still a bit confused by the balance thing though. This is an inferior version of keen mind or a clock, an almost useless alarm, and an inferior version of the message spell. Not exactly balance destroying.

I agree that taken to the extreme it can be ridiculous but the cost and functionality of the earpiece in this thread is not that.

Originally Posted by JackPhoenix

As far as I'm concerned....
- the object has to be big enough to form the mouth, which is a copy of the caster's mouth. No grains of sand or similar nonsense.
- MM has no Perception. It can react to visible and audible triggers, but it can't see anything behing heavy concealment, hear nothing clearly audible from its position and it can't notice any sneaking creatures.
- It can reacto to visible and audible triggers, but nothing else. Not the passage of time, not creature types, and not any extra conditions.

Your world, your rules. As I’ve said, trying to put strict restrictions on the spell conditions is kind of pointless. You really want to put them on the final result. I think this aligns with the rulings not rules approach of 5e better anyway but it’s also just much much more practical at the table.

The first point only affects the size of the object and not by a lot. Eg. Instead of an earpiece you now have a deck of cards. It’s a restriction but it changes very little in terms of balance or functionality.

The second point is entirely reasonable but doesn’t prevent a lot of the potential “abuse”. (In this case the audibility restriction means the PCs could learn hand signs or pick up the message cantrip. Hardly OP compared to having them drop 500gp for monotone, single volume, “speech” within 30ft. ) BTW I think you’re missing a “not” before the “clearly audible” part.

The time aspect of the third point is entirely circumventable (eg with a second magic mouth that says “tick”) as long as you still allow any condition that involves counting or clockwork exists in your world. Eg. If you can trigger when a bell has been rung twice. Now your basic MM functions like “when an adventurer enters this room for the first time” are in question (and that’s kind of staple of how the spell is used in dungeons)

I’m curious what you consider “extra conditions”?

Limits like “the passage of time” are going to cause issues. You’re going to get into a dreaded “physics” discussion because stuff like sound and movement require the passage of time to be detected. So your audio triggers just are not possible blah blah blah. Again - I strongly advise a DM to judge based on the functionality of the whole rather than try and alter the rules with additional conditions. That way either breaks the normal use of the spell, or accidentally grants it OP abilities in the name of “consistency”.

This is a pretty big derail from the design and critique I think this thread was about. Baphomet has said they’re trying to steer away from the theory (what is possible) and stick to a practical example use (how to make this earpiece functional).

**Willowhelm** · 2022-05-21, 05:08 PM (ISO 8601)

Originally Posted by Willowhelm

For the arcane lock clock I was not imagining an entire clock using arcane locks for display. Essentially you’d build a normal mechanical clock/watch but the quality of the time keeping can be a little more slap-dash because an arcane lock (triggered by the MM speaking the password at a prescribed rate) will only unlock for exactly 1 minute. You can thus have a mechanism which would run fast normally, but is limited by the lock. You still require too much other clockwork technology to make this work as you said that clockwork doesn’t really exist in this campaign. (IF you rule that the mouth actually moves and is not just illusory, then you can eliminate all the hard parts of a clock’s internals and it is very easy to make a clock without any arcane lock or clockwork technology)

Apologies for the double post and the self quote. I thought enough time had passed that an edit would be lost and confusing.

Arcane (C)Locks!

I thought about this and came up with a handful of designs for a minute-accurate clock which does not require any particular clockwork knowledge or skills.

For a stationary option you can make a water clock (like a bamboo rocking fountain) with an overflow/trickle down balance kind of mechanism similar to this:

(Obviously with no clock or ball-raising arm).

You have the top lever/arm rest on, or be part of a gate with arcane lock on it. (if resting on the gate it would need to be sprung so that it would shut again when the arm swings back up.
A magic mouth is set to say the password every 5 mins so the lock will open (or whatever period you like... just more than a minute)
The top lever "fills" in a time period that is greater than 1 min (so it doesn't double pour), but under your trigger time (so it is full before it triggers - overflow goes out the back/side).
Each time the gate opens, a consistent volume of water pours out into the next level. Levers levers levers, gravity gravity gravity... super basic clock. No gears, "clockwork", fine tooling or anything like that. One magic mouth. One arcane lock. Make it with bamboo. Make it with pythagorean siphons.. whatever floats your boat or fits your campaign setting. It just works by gravity, balance, and an arcane lock/Magic mouth pair.

(This can obviously work with balls from a hopper too... but making spheres is harder than cutting bamboo, and even without a convenient stream you can replenish your water one with a quick Create or Destroy Water)

The second design is more like what most people would think of as a "clock". (Clock hands going around a clock face). If you can make a coil spring or similar it can be portable. If not, literally anything that can apply a constant turning force will do. (eg. Rock on a cord wound around axle, tiny servant for 8 hours). You'll want to be able to make gears with a 60:1 ratio (or a series of gears) but that is (in my opinion) totally possible technology in most dnd campaign settings.

If you can't make a 60:1 ratio gear train you can do without gears entirely and just have a ton of arcane locks and magic mouths but then your costs get pretty silly.

Spring powers axle.
Axle has a protrusion/obstruction that comes into contact with a locked, spring loaded, gate.
Every minute, the gate opens with password from MM. Turning force from spring is greater than the gate spring, obstruction passes through and door shuts behind it.
Axle protrusion meets second AL/MM pair half a rotation later and stops. This gate is also on a 2 min cycle, offset by a minute. Every time one gate unlocks, the other is locked.
Now you have an axle which turns exactly half a rotation every minute.

If you can do a 30:1 gear ration this can give you a minute hand. Either duplicate the whole set up with different timings or do a 60:1 gear ratio from that to get your hour hand.

I could draw pictures to make it clearer but i probably wont unless requested.

Anyway... that is a permanent-until-dispelled pocket watch from 2 arcane locks and 2 magic mouths. It doesn't rely on any strange rulings or questionable functionality of either spell, and it doesn't require clockwork in your campaign setting. Thats 70Gp + materials.

That's why i'd be fine as DM letting someone build a speaking clock for... however many hundred Gp this bead-based solution comes out to? The outcome is the same, even if the means are different.

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