Can I do this with the spell detect Magic

[Sir cryosin]

Detect magic shows you Aurora's of magic and allies you distinguish what kind of magic is being used. can I cash to detect magic and see a invisible creature by seeing the the illusion magic around it.

[PeteNutButter]

Detect Magic specifies any visible creature or object.

[Sir cryosin]

Well I should read befor asking haha. Thanks.

[ZX6Rob]

Pretty sure the intended answer to this is "no", but I don't know if there's any actual rules text to support it. I know that's certainly how I'd rule it as a DM, if that helps in the slightest.

The existence of "See Invisibility" as a spell -- and, specifically, a spell that comes online at a higher level than Detect Magic (albeit by one) is evidence enough for me that the designers intended that the ability to defeat invisibility ought to "cost" at least that much.

In terms of fluff, you always have a bit of leeway. If I were pressed, I'd come up with something like, well, the casting of the spell includes the things the person is wearing or carrying, too, so it's clearly capable of shielding things other than just the caster from sight. Perhaps part of the spell is that the arcane signature is likewise hidden. If you want to see that, you need a particular refinement of the spell -- one that is "tuned" for that specific "wavelength", for want of a better term. That'd be See Invisibility.

[Shining Wrath]

What if something is invisible due to some other reason than magic? Are Invisible Stalkers naturally invisible? Maybe there's no aura to see.

Maybe what you would detect was that there was something magic "in that direction". As noted, usually Detect Magic works on an item you look at specifically.

[Toofey]

In yon olden days (2nd ed, I think 1st too) there was language that it revealed magic was at play but not the location of the invisible creature, in the current RAW this has been more directly addressed as previously noted.

[Reynaert]

Detect Magic specifies any visible creature or object.

Only in the bit where you use an action to see the aura to determine the type of magic.

So if you're running Detect magic and a (magically) invisible creature is within 30ft, you do sense it, but there is no aura to be seen.

[NNescio]

Only in the bit where you use an action to see the aura to determine the type of magic.

So if you're running Detect magic and a (magically) invisible creature is within 30ft, you do sense it, but there is no aura to be seen.

You sense the presence of magic within 30 ft. You only know if magic is present or not. Nothing tells you whether it's an invisibility effect, much less an illusion, and you can't pinpoint the specific location of the source of magic either. For all you know it could just be background static (from a hallowed tomb, for example).

Spells that allow you to detect the location of things you sense have specific language to that effect, like Detect Evil and Good (e.g. "as well as where the creature is located").

[Reynaert]

You sense the presence of magic within 30 ft. You only know if magic is present or not. Nothing tells you whether it's an invisibility effect, much less an illusion, and you can't pinpoint the specific location of the source of magic either. For all you know it could just be background static (from a hallowed tomb, for example).

Spells that allow you to detect the location of things you sense have specific language to that effect, like Detect Evil and Good (e.g. "as well as where the creature is located").

I agree with your first two points but disagree with the third: From the wording of the spell, you can use your action and then you see an aura around any visible object/creature that bears magic. Therefore, if you use that action and see no auras, whatever bears the magic you detected must logically be invisible (to you). "Background static" would also get an aura, since you can see whatever has that background magic (such as that hallowed tomb).

[Shining Wrath]

You'd get the same effect from a druid transformed into a gnat, too. Or if a stone in the wall had been removed from a hallowed tomb 5,000 years ago and used in construction of this structure. "There's magic in that direction". That's it.

[Zanthy1]

You'd get the same effect from a druid transformed into a gnat, too. Or if a stone in the wall had been removed from a hallowed tomb 5,000 years ago and used in construction of this structure. "There's magic in that direction". That's it.

This is exactly how I do it. Players enter the Lich's lair, "I cast detect magic" well son, there is most certainly magic, everywhere.

Its much more effective in areas where you wouldn't expect magic, like a random inn located near the slums. You see a guy who is getting excessively lucky with his dice (or ladies), maybe detect magic to see if he could be up to something.

[Reynaert]

You'd get the same effect from a druid transformed into a gnat, too. Or if a stone in the wall had been removed from a hallowed tomb 5,000 years ago and used in construction of this structure. "There's magic in that direction". That's it.

With a gnat you would see a tiny tiny halo around the gnat, and with the stone in the wall from a hallowed tomb, you'd see a halo around the stone.

[JellyPooga]

Only in the bit where you use an action to see the aura to determine the type of magic.

So if you're running Detect magic and a (magically) invisible creature is within 30ft, you do sense it, but there is no aura to be seen.

This. You'll know that there's magic afoot, but won't be able to locate the source because it's invisible to you; it could be a magically invisible creature, a magic item that's out of sight behind a wooden panel or any number of things, but you know there's something magical that you can't see within 30ft of you once you take an action to try and locate that aura. All you get immediately upon casting the spell is the knowledge that there's some kind of magic present within 30ft; which given adventurers and their habit of collecting magical items and effects, isn't a particularly useful piece of information. Be sure to get your companions to back off a bit before using Detect Magic, otherwise you'll only get a bunch of false (well, unwanted) returns and discover little new, if you're using it as a "magic-finder" (is there any magic stuff here?) as opposed to a "magic-checker" (is this thing here magical?).

[Joe the Rat]

Process of elimination.

The process being that after you get everyone else 30 feet away ("yep, still magic here"), the invisible creature gets a free go at eliminating the isolated caster.
This be a good approach for finding - or at least detecting - magically hidden objects.

What I have done is let players take an action to filter out known magics - accounting for the items and effects that you know about, is there something else present? At the very least, I'd let the caster ignore his own items, particularly if they are attuned.

Nystul's Magic Aura also comes on at 2nd level - a 24 hour spell that can, among other things, hide magic auras. I don't think you'd need to add that aspect to invisibility (can't see that an illusion is present if you can't see the object), but that could be a wicked combination if it could account for a spell cast on a creature.

How does Detect Magic interact with illusions (minor illusion or silent image, for example)? You can sense magic is present, but if there isn't an actual object to have an aura, what can you sense?

[NNescio]

How does Detect Magic interact with illusions (minor illusion or silent image, for example)? You can sense magic is present, but if there isn't an actual object to have an aura, what can you sense?

Well, I guess per RAW, you only sense the presence of magic (for minor illusion and the "image" line of spells), as there's no object or creature for the aura to be attached to.

Other illusions that are cast on a creature or object (or ongoing 'illusions' that create creatures or objects like Creation and Simulacrum) would ping on auravision though.

[Dalebert]

Keep in mind, Detect Magic works through a certain amount of material as specified in the spell. The stone could be behind other stones and might still trigger it. The gnat could be on the other side of the leaf of a bush and have total cover. It's quite possible or even likely that there's something magical that's blocked from your sight but not from the spell effect.

That said, it could still work as a poor man's invisible alert system. It would ping if something invisible approached. However, it would also ping if someone walked up with a magic item and it won't show an aura if it's covered, like if their cloak is concealing a sword or their Hat of Disguise is covered by a magical disguise. It would also ping if you walk by something magic that's just outside of your LOS.

[JellyPooga]

Keep in mind, Detect Magic works through a certain amount of material as specified in the spell. The stone could be behind other stones and might still trigger it. The gnat could be on the other side of the leaf of a bush and have total cover. It's quite possible or even likely that there's something magical that's blocked from your sight but not from the spell effect.

That said, it could still work as a poor man's invisible alert system. It would ping if something invisible approached. However, it would also ping if someone walked up with a magic item and it won't show an aura if it's covered, like if their cloak is concealing a sword or their Hat of Disguise is covered by a magical disguise. It would also ping if you walk by something magic that's just outside of your LOS.

To think of it another way; Detect Magic works somewhat like the motion detectors in the film Aliens. You know there's something in range, but without verification you don't know where anything is. At least until you take a look above the ceiling tiles...

Private Hudson: [knowing that the Aliens are close, Hicks and Vasquez are welding the door shut] Movement. Signal's clean. Range, twenty meters.
Ripley: They've found a way in, something we've missed.
Corporal Hicks: We didn't miss anything.
Private Hudson: Seventeen meters.
Ripley: [checking the tracker] Something under the floor, not in the plans, I don't know.
Private Hudson: Fifteen meters.
Newt: Ripley.
Corporal Hicks: Definitely inside the barricades.
Newt: Let's go.
Private Hudson: Twelve meters.
Ripley: That's right outside the door. Hicks, Vasquez get back.
Private Hudson: Man, this is a big .... signal.
Corporal Hicks: How are we doing, Vasquez? Talk to me.
Private Vasquez: Almost there.
[they weld the door shut and step back away from the door]
Private Vasquez: They're right on us.
Corporal Hicks: Remember: short, controlled bursts.
Private Hudson: Nine meters. Seven. Six.
Ripley: That can't be; that's inside the room.
Private Hudson: It's reading right man, look!
Corporal Hicks: Then you're not reading it right.
Private Hudson: Five meters, man. Four. What the hell?

...and if you can engineer a scenario even half as good as this one with Detect Magic, you are the Best. GM. Ever! (or Player, I suppose; getting Detect Magic to work like a magical motion detector would take some effort)

[Dalebert]

...and if you can engineer a scenario even half as good as this one with Detect Magic, you are the Best. GM. Ever! (or Player, I suppose; getting Detect Magic to work like a magical motion detector would take some effort)

A little tricky when the range is 30 ft and that's how fast most creatures move in a single round and can still attack.

[JellyPooga]

A little tricky when the range is 30 ft and that's how fast most creatures move in a single round and can still attack.

Who said we're necessarily defending against attack?

Hmm....let's see here...

Nothing I know of extends the range of Detect Magic, so to get a range of 20m (around 60ft), we'd need a series of at least 2 casters;

|--30ft--|Caster A|--30ft--|--30ft--|Caster B|--30ft--|

However, the more caster we have, the closer together the casters are and the more overlap of Radii-of-Effect we can get, the more precise a "reading" we can get;

|-15ft-|-15ft-|A|-15ft-|B|-15ft-|C|-15ft-|-15ft-|

In this scenario, if only A or C detect it, we know it's at the furthest reach of our arrangement on either side. If B can detect it as well as either A or C, but not the other, then we know it's within 5m the other side of A or C (whichever one detects) from B. If all three detect it, we know it's somewhere between A and C.

The more casters you have and the closer together they are, the finer-tuned the detector is. Hudson was detecting at 3m intervals to begin with and 1m at the end; I don't think we're going to achieve that without a heap of apprentice lvl.2 Warlocks (hmm...that's an idea...), but we can get close with a party of 4.

This is assuming a straight line. The world is 3D, so a grid or "venn diagram" style arrangement of overlapping AoE is probably preferable and with it, you could probably get a fairly accurate "fix" on the location of an invisible infiltrator that's trying to sneak past your group.

[BiPolar]

I'm still not sure how an invisible creature gets around the "visible object" clause.

I also don't understand how an object can be visible if it's behind wood. Unless that clause is purely to prevent detection of things invisible.

[JellyPooga]

I'm still not sure how an invisible creature gets around the "visible object" clause.

I also don't understand how an object can be visible if it's behind wood. Unless that clause is purely to prevent detection of things invisible.

The "behind wood" clause applies to detecting the presence, but not the location of the subject. So a magic item behind a thin wooden panel or covered by a heavy drape would ping upon casting the spell (detecting the presence), but upon taking an action to see magical auras, you'd get nothing; the item isn't visible to you, so you can't see the aura around it.

With multiple casters, detecting the location of an invisible creature would depend on who is detecting magical presences at a given time and how the AoE of the spells are arranged geographically. In my above example, we can determine which 15ft area an invisible creature is, but not his precise location (our "motion detector" isn't that finely tuned).

[BiPolar]

The "behind wood" clause applies to detecting the presence, but not the location of the subject. So a magic item behind a thin wooden panel or covered by a heavy drape would ping upon casting the spell (detecting the presence), but upon taking an action to see magical auras, you'd get nothing; the item isn't visible to you, so you can't see the aura around it.

With multiple casters, detecting the location of an invisible creature would depend on who is detecting magical presences at a given time and how the AoE of the spells are arranged geographically. In my above example, we can determine which 15ft area an invisible creature is, but not his precise location (our "motion detector" isn't that finely tuned).

I still don't understand how you are getting around the "visible creature or object" requirement.

[JellyPooga]

I still don't understand how you are getting around the "visible creature or object" requirement.

In what regard? That particular component of the spells effect only applies to taking an action to see the magical auras surrounding things that you can see. If you can't see the subject, you can't see it's aura either. An Invisible creature is, well, invisible, so you can see neither the creature nor its aura.

Detecting the presence of magical auras is not predicated on being able to see them, however. It is dependent on there not being a great lump of dirt or a thin sheet of lead between you and the source (hence that criteria included in the spell).

So you can detect the presence of an invisible creature ("There's something magical within 30ft of me..."), but not the location ("...but I'm not picking up any other readings. Look out guys, there may be someone invisible").

Does that clarify things?

[BiPolar]

In what regard? That particular component of the spells effect only applies to taking an action to see the magical auras surrounding things that you can see. If you can't see the subject, you can't see it's aura either. An Invisible creature is, well, invisible, so you can see neither the creature nor its aura.

Detecting the presence of magical auras is not predicated on being able to see them, however. It is dependent on there not being a great lump of dirt or a thin sheet of lead between you and the source (hence that criteria included in the spell).

So you can detect the presence of an invisible creature ("There's something magical within 30ft of me..."), but not the location ("...but I'm not picking up any other readings. Look out guys, there may be someone invisible").

Does that clarify things?

Ah, I get it. So the Detect Magic tells you there is magic in the area. If you take an action, then no aura is seen and no information on school is provided (presumably that's based on the aura, or it is i my mind.)

That could lead to a lot of possibilities which include someone invisible. But the player only knows that they have detected something but can't see an aura for whatever reason.

Is that right?

[JellyPooga]

Ah, I get it. So the Detect Magic tells you there is magic in the area. If you take an action, then no aura is seen and no information on school is provided (presumably that's based on the aura, or it is i my mind.)

That could lead to a lot of possibilities which include someone invisible. But the player only knows that they have detected something but can't see an aura for whatever reason.

Is that right?

You got it.

[BiPolar]

You got it.

clearly i need more caffeine.