How does trapfinding work

[D.M.Hentchel]

So one of newer players asked the simple question after successful disabling a symbol of death, "How did I do that?"

And I had no idea what to tell her.

So I ask you Playgrounders? How do you disable a magical trap?

[exelsisxax]

Deface any sort of writing or engraving sufficiently to disable its function without triggering the effect?

[Troacctid]

I usually do it by casting dispel magic, but to each her own. :smallwink:

Unlike most spells, magic traps that can be disabled always have some sort of flaw that a clever dungeoneer can exploit. Scratch out the sigils in the right places and the whole thing falls apart, y'know? As a DM, I would allow my player to narrate what they are doing to disable the trap and allow them to be creative in their explanation.

[Crake]

I've always wondered this myself. How do you disable a magical symbol trap for examble, when it's set to trigger from anyone entering within say, 30 feet of it? I mean, finding it is all well and good (hopefully you didn't need to enter within 30ft of it to be able to find it, for example if it's around a corner and detecting it would immediately trigger it), but circumstances like that, they seem impossible for the rogue to achieve. I've always just ruled it that the rogue wasn't able to actually disable it, but then, the rogue has usually been an NPC in my games.

[ericgrau]

For a magic rune yeah he figures out how to disturb or cover the rune without triggering it. Actually it says in the symbol spell description all you have to do is cover it and it's disabled. Easy peasy.


I've always wondered this myself. How do you disable a magical symbol trap for examble, when it's set to trigger from anyone entering within say, 30 feet of it? I mean, finding it is all well and good (hopefully you didn't need to enter within 30ft of it to be able to find it, for example if it's around a corner and detecting it would immediately trigger it), but circumstances like that, they seem impossible for the rogue to achieve. I've always just ruled it that the rogue wasn't able to actually disable it, but then, the rogue has usually been an NPC in my games.

That's not one of the trigger options, though you can get close. The spell does allow anything observable. So if it "sees" anything get near it might go off. Summons or other tests might still test for it. Thrown object+detect magic could see the AOE. The rogue could use a mirror and throw a tanglefoot bag at it to cover and disable it. More adventurers need to carry mirrors btw, and/or the DM needs to bring in more creative traps and sneaking around. Or heck, throw 150 hp in summons at it.

Let's say we have an actual proximity trap, not symbol of death. A hypersensitive finely balanced pin responds to subtle changes in the air pressure and vibration. It falls onto a hidden rune which activates a fireball. If highly sophisticated it might have a spring-loaded reset, though even then the rune can only trigger every so often. I would not let a rogue disable or even find a proximity trap by walking up to it. Not without triggering it. Nor can he wave his hand and rogue it at the edge of its range.

Instead he might try to search the doorway and I'd say "The air is unusually still in this room. It is free of dust, ventilation and any object that might topple. You think there may be a proximity trigger in here that they are trying not to accidentally activate, or else the room is meant to scare rogues by looking like a trap." He says he wants to disable it, I say you can't see or disable it from here. So he throws an object in the room, woosh it gets fireballed. He thinks, tries another object after some time. It gets fireballed. He tries another object right away. No fireball. He peers carefully and sees a crack in the wall where air pressure might be received. So he thinks, hmm, can I gum that up with rapidly thrown objects (no roll), run in after a fireball and seal off the opening real quick (roll disable device with small penalty, needs gear/tools), or run in after a fireball and break the door down to the exit (roll to destroy door only).

[D.M.Hentchel]

So the entire reason I bring this up is that I am removing disable device entirely from the game (putting the non-trap functions of it into Knowledge [engineering]). While mechinical traps usually offer an interesting problem solving scenario I was have trouble with self reseting magical traps and certian spells.

The covering runes thing is very helpful.

It seems I should just increase the cost/cr of self-reseting magic traps.

Still Alarm triggers seem extremely difficult to trick and detect good seems extremely difficult for a rogue to trick.

I guess I could make relitively cheap items that have an aura (magical or alignment) that a rogue could toss infront of the sensor to trigger it. Then just up the CR/cost of the Alarm trigger.

Any other thoughts guys?

[Troacctid]

You can scuff runes from a distance pretty easily if you're any good. I mean, that's what 10-foot poles are for, after all, and it's not hard to improvise the same functionality even if you don't have one handy.

[Necroticplague]

Depends on the trap. Each one is different, and has different methods of disabling/disarming. Trapfinding is a generalized knowledge about these things enough that you can extrapolate to find out based on known ones. That's why the two relevant skills are INT based. It's you figuring out. Sometimes, you might simply figure out a blind spot in the symbols vision based on its detection runes. Sometimes, it's knowing which part is equivalent to the red wire. Sometimes, it might be a combination. It really depends on the details of the trap.

[ericgrau]

So the entire reason I bring this up is that I am removing disable device entirely from the game (putting the non-trap functions of it into Knowledge [engineering]). While mechinical traps usually offer an interesting problem solving scenario I was have trouble with self reseting magical traps and certian spells.

The covering runes thing is very helpful.

It seems I should just increase the cost/cr of self-reseting magic traps.

Still Alarm triggers seem extremely difficult to trick and detect good seems extremely difficult for a rogue to trick.

I guess I could make relitively cheap items that have an aura (magical or alignment) that a rogue could toss infront of the sensor to trigger it. Then just up the CR/cost of the Alarm trigger.

Any other thoughts guys?
Ah ok. BS a way that every trap works so that the players have a way to disable it. Tell them more about it as they examine it.

Yeah read the spell for built in ways to disable it. For runes you could make up that you have to wipe away the correct parts of a rune, similar to cutting the right wire when disarming a bomb. This may involve knowledge or spellcraft checks.

[Nifft]

Yeah read the spell for built in ways to disable it. For runes you could make up that you have to wipe away the correct parts of a rune, similar to cutting the right wire when disarming a bomb. This may involve knowledge or spellcraft checks.

"Cut the green ligature."

"No, you need to cut the red accent!"

"Guys I'm using Darkvision, there's just gray."

[Troacctid]

Ah ok. BS a way that every trap works so that the players have a way to disable it. Tell them more about it as they examine it.

Yeah read the spell for built in ways to disable it. For runes you could make up that you have to wipe away the correct parts of a rune, similar to cutting the right wire when disarming a bomb. This may involve knowledge or spellcraft checks.
Specifically, it involves a Disable Device check (and NOT a Knowledge or Spellcraft check), as indicated by the rules, which are very explicit on the matter.

[OldTrees1]

I think of trap disarming like Haley with the runed door (http://www.giantitp.com/comics/oots0867.html). Essentially traps, be they mechanical or magical, are just a network with sensors for inputs and spell runes for outputs. Adding or removing connections as well as altering internal runes/gears would change the device in the same way that altering a computer chip would.

[Crake]

That's not one of the trigger options, though you can get close. The spell does allow anything observable. So if it "sees" anything get near it might go off. Summons or other tests might still test for it. Thrown object+detect magic could see the AOE. The rogue could use a mirror and throw a tanglefoot bag at it to cover and disable it. More adventurers need to carry mirrors btw, and/or the DM needs to bring in more creative traps and sneaking around. Or heck, throw 150 hp in summons at it.

I bring this up because my players actually recently came up against something like this. And yes, you can set a symbol's trigger to proximity if you wish, the given triggers are only the "default" triggers, later on it goes on to say that you can allow any trigger you want. Also worth noting that a permanencied symbol that doesn't have a HP limit, like say, symbol of insanity (this corridor had 5 various symbol traps in it) can't be overcome by just tossing summons at it (though that's how they got past the death rune XD just as you mentioned). So triggering the rune, then waiting it out is not a solution, and you can't get close enough to disable it without risking triggering it. How is a rogue supposed to disable that without using a ranged dispel magic, that's what confuses me.

[Efrate]

Considering Rogues are already a fairly poor op class, going for gritty realism traps using real world physics is a big no no in my book. He's a rogue, its what he does. He is lucky/good enough to find that tiny little line of approach that with light steps and careful footing doesn't trigger it until he is upon it. Otherwise you have made proximity triggers and the such functionally undisarmable, without a bunch of other resources, or a spellcaster.

There is a scene, in Ocean's 13 I believe, where a fabrage egg is in a museum and its security is a bunch of semi-random lasers that constantly move at all angles across a passage, and the person who goes to steal it dances, bounces, dips, etc. to get around all of them which is supposedly impossible. Your rogue is that guy, he's that good. He has perfected a level of bodily control and a method of approach which is unimaginable to anyone else, and he uses every little minute dip and crack in the floor to approach with his skills honed from years of experience to just not set it off. Because he is that good.

Real world physics and DnD do NOT play well together. Discard it immediately, cause magic. If that unacceptable I don't know what to tell you, but you may wish to look at other systems, because that particular combination will never line up well.'

tl,dr: He's a rogue, its what he does. That's why.

[OldTrees1]

I bring this up because my players actually recently came up against something like this. And yes, you can set a symbol's trigger to proximity if you wish, the given triggers are only the "default" triggers, later on it goes on to say that you can allow any trigger you want. Also worth noting that a permanencied symbol that doesn't have a HP limit, like say, symbol of insanity (this corridor had 5 various symbol traps in it) can't be overcome by just tossing summons at it (though that's how they got past the death rune XD just as you mentioned). So triggering the rune, then waiting it out is not a solution, and you can't get close enough to disable it without risking triggering it. How is a rogue supposed to disable that without using a ranged dispel magic, that's what confuses me.

Well a properly educated rogue (http://archive.wizards.com/default.asp?x=dnd/ex/20061106a&page=2) can merely be crafty and disable the rune while standing 60ft away. However lesser rogues would have to settle for covering* the rune from outside** the 60ft radius and then walking up to it to disarm it at normal arm's length.

Although I did not find where it gave an open ended expansion of the flexibility of the triggers. There is a paragraph about "You can also set special triggering limitations of your own." but that restricts rather than expands the triggers. Which paragraph(s) should I reread?

*

Covering or hiding the rune renders the symbol of death ineffective, unless a creature removes the covering, in which case the symbol of death works normally.
But be warned!

In this case, “reading” the rune means any attempt to study it, identify it, or fathom its meaning. Throwing a cover over a symbol of death to render it inoperative triggers it if the symbol reacts to touch.

**

Regardless of the trigger method or methods chosen, a creature more than 60 feet from a symbol of death can’t trigger it (even if it meets one or more of the triggering conditions, such as reading the rune).

[CasualViking]

Well a properly educated rogue (http://archive.wizards.com/default.asp?x=dnd/ex/20061106a&page=2) can merely be crafty and disable the rune while standing 60ft away. However lesser rogues would have to settle for covering* the rune from outside** the 60ft radius and then walking up to it to disarm it at normal arm's length.

Although I did not find where it gave an open ended expansion of the flexibility of the triggers. There is a paragraph about "You can also set special triggering limitations of your own." but that restricts rather than expands the triggers. Which paragraph(s) should I reread?

*

But be warned!


**

Yeah, there's no such thing as a hidden proximity symbol. When created, it gets on or more of the following triggers: " looks at the rune; reads the rune; touches the rune; passes over the rune; or passes through a portal bearing the rune".

It specifically can't be hidden: "To be effective, a symbol of death must always be placed in plain sight and in a prominent location. Covering or hiding the rune renders the symbol of death ineffective".

Then there's this part: "You can also set special triggering limitations of your own. These can be as simple or elaborate as you desire. Special conditions for triggering a symbol of death can be based on...". These are not replacements for the trigger rules, but refinements. It's not "when a non-dwarf is within 60'", because being within 60' was never a legit trigger; it's "when a non-dwarf looks at the rune".

[Ethernil]

The rogue is already somewhere between mediocre and bad on the power scale. Stop nerfing it with house rules. In a game I played the dm demanded that I roll one cause the party needed it as he said. Later I found that in his games sneak attack doesn't trigger off flanking since "the enemy is aware of your presence so it is not a sneak attack", skill checks were tuned around my skill points because "it wasn't fun if I needed to roll 2 or 3 to succeed" and I had to explain how I disable device etc through role playing and if I didn't explain it correctly I failed the check. This kind of gameplay applied to other skills. Needless to say I suicided my character and rerolled a 6 intelligence fighter. I had much more fun in his game with that.

[Mordaedil]

So one of newer players asked the simple question after successful disabling a symbol of death, "How did I do that?"

And I had no idea what to tell her.

So I ask you Playgrounders? How do you disable a magical trap?

"You tell me. How did you disable the magical trap?"

Let the player think in her own shoes. Maybe she uses a mirror to reflect the deadly magic of the symbol of death while she triggers the spells with a stick. She succeeded, but only she would know how she did it. What does she have on her, what could she use and what would be useful in disabling the trap? Give her ideas, but ultimately leave it to the player to know how.

[Crake]

Well a properly educated rogue (http://archive.wizards.com/default.asp?x=dnd/ex/20061106a&page=2) can merely be crafty and disable the rune while standing 60ft away. However lesser rogues would have to settle for covering* the rune from outside** the 60ft radius and then walking up to it to disarm it at normal arm's length.

Although I did not find where it gave an open ended expansion of the flexibility of the triggers. There is a paragraph about "You can also set special triggering limitations of your own." but that restricts rather than expands the triggers. Which paragraph(s) should I reread?

*

But be warned!


**

Huh, I always took the wording to mean that you can set the trigger limitations to what you want, including proximity. I can see how you might interpret it in your way, but the way I've always read it is that you can set the trigger limitations to what you want, including expanding the limtiations from the default to something more encompassing. Because by default they're set to one limitation, but you can expand on those limtiations to whatever you want. As it says, these can be as simple or as elaborate as you want, and I've taken that to mean that you could for example, say "If a living creature comes within 10 feet" or "if bob opens the second drawer of my desk" and official modules seem to somewhat support that idea, as the ones I've read have used triggers like those.

[OldTrees1]

Huh, I always took the wording to mean that you can set the trigger limitations to what you want, including proximity. I can see how you might interpret it in your way, but the way I've always read it is that you can set the trigger limitations to what you want, including expanding the limtiations from the default to something more encompassing. Because by default they're set to one limitation, but you can expand on those limtiations to whatever you want. As it says, these can be as simple or as elaborate as you want, and I've taken that to mean that you could for example, say "If a living creature comes within 10 feet" or "if bob opens the second drawer of my desk" and official modules seem to somewhat support that idea, as the ones I've read have used triggers like those.

Ah. I still fail to parse it your way, but that is mostly irrelevant. The idea of a proximity triggered runic trap is well within something a DM could add and expect a rogue to disarm.

Remember that all traps can be thought of as containing the of the following parts:
Sensors (how the trap detects the details relevant to its triggers)
Logic matrix (how the trap converts observation into triggers and triggers into variable output)
Output (how the trap effects the world)
To disarm a trap one usually needs to avoid detection. Although if you can still disarm the trap if you are faster than the logic matrix can tell the output to output. However slow to activate traps can often be outrun. So what kind of sensors is the trap using and how to avoid them (Arcane Sight is a common magical trap sensor)? Once you know the sensors you can either avoid them by not being the kind of thing they pick up or you can trick the sensors into thinking you are not the kind of thing they pick up.

Put it together:
The following is a nasty trap I have not yet put into a game. 25ft feet underneath a hallway is a bleakborn (undead from Libris Mortis) submerged in holy water. The bleakborn has instructions to pull a lever activating a spell clock of Mass Suggestion("Sitting down would be more comfortable").
Sensor: Living creatures not immune to cold damage within 30ft of the Bleakborn
Logic Matrix: Bleakborn pulls a lever on its initiative
Output: Mass Suggestion to keep the targets in range
To disarm this trap you would need to have someone not register as "living & vulnerable to cold damage" while they disarm the spell clock, the lever, or destroy the bleakborn (I suggest the spell clock).