Spelltrap - how to identify?

[Zhari]

Hello folks.
After reading about traps in Xanathas Guide today, I've got a lil question.
If I place a spell as a trap in a chest. For ex you open it without saying the password a fire ball explodes. Thats the trigger.
But how is the players group able to detect it? Magic traps arent detectable with perception Id say . cuz u cant hear,smell or See the trap. Disarming it with arcana check OK,or maybe a disspell magic.
Any tips in what you wanna hear from the group to tell Them about a poss thread? Or do they have to have a clue and cast detect magic?

THX for ur help! :)

[BobZan]

Put a Perception Check so he can notice the trigger, DC 15 for a crude trap, 20 for a nice one, 25 for an exceptional one.

To disable it, put the same Arcana DC or a Dispel Magic.

Traps should be a doable challenge to overcome. If you create the hidden mechanic that a player should try Arcana instead of Perception to identify given Magical Trap the nice thing to do is to inform the new rule to your players, else it won't be fun nor challenging.

[OldTrees1]

I have always run it as proficiency in thieves tools means you have the know-how to detect and disarm all kinds of traps1. This includes noticings and reading traces of whatever is holding the spell and the triggering mechanism for releasing that hold. Sometimes this is an engraved circle or runes. Sometimes it is a detection spell watching a taut thread. Sometimes it is just intuition/deduction about where the invisible/inaudible sensor ought to be if the trap were made right.

1. This matches up with literature in the genre and mechanics in previous versions

[Unoriginal]

Hello folks.
After reading about traps in Xanathas Guide today, I've got a lil question.
If I place a spell as a trap in a chest. For ex you open it without saying the password a fire ball explodes. Thats the trigger.
But how is the players group able to detect it? Magic traps arent detectable with perception Id say . cuz u cant hear,smell or See the trap. Disarming it with arcana check OK,or maybe a disspell magic.
Any tips in what you wanna hear from the group to tell Them about a poss thread? Or do they have to have a clue and cast detect magic?

THX for ur help! :)

The question is HOW are you placing a trap in a chest. Do you enchant the chest? Do you use another spell to make the spell stay on and activate only in X circumstences?

[Tanarii]

But how is the players group able to detect it? Magic traps arent detectable with perception Id say . cuz u cant hear,smell or See the trap. Disarming it with arcana check OK,or maybe a disspell magic.Undetectable traps usually aren't much fun for players.

I mean, they can use Detect Magic, which is a ritual.

But if you're going to make magic traps that are only detectable with Detect Magic, recommend you start off with some small ones to get them used to the idea.

Here's my rules for traps in general, which can be adapted to magical traps if you're okay with that:
Passive Perception - used to notice something is off somehow. Usually related to the trigger or method of doing damage, and usually visual. Never just reveals a trap. It gives a hint.
Passive Investigation - used identically to passive perception (including the same value) if the player tells me they are searching for traps. Represents deductive reasoning applied directly to looking for traps.
Investigation check - If the player investigates the hint in a way that makes sense, this provides further information. Not perfect details.
disabling - if the player figures out what's needed to disable a trap but it's not automatic, then they can make a thieves tools check to disable.
player skill - if the player figures out how to bypass the trap, or disable it in a way that automatically succeeds, let them.

Remember a by-passed trap is still there, and a disabled trap is now disabled. This can mean consequences if the party retreats or is being tracked or otherwise pursued.

IMO finding a trap should always present the players with interesting choices once they are found. Any trap that's just a "gotcha", as in find it via passive perception and disable with a thieves tools check or take damage, are boring. (That said, this is still a step up from old-school "gotchas" of read the DMs mind or die.)

[Laserlight]

For ex you open it without saying the password a fire ball explodes. But how is the players group able to detect it?

When the fireball goes off, you detect the trap.

[MrStabby]

I use perception to give the players clues that something is there then:

If it is a physical trap investigation to find it

If it is a spell then either Arcana Check or Religion Check to find it, depending on type (things like curses and the like tend to me more religion)

Niche examples of traps including hostile animals or plants can be detected through nature check



Sometimes a history check will provide legends about where in a dungeon famous adventurers dies or the type of peril they faced.