i fucking hate writing ...
Staff member
  1. Traps should have clues they exist, in most cases.
    1. At higher levels traps can be more deadly and have few to no clues because characters have access to a fuck ton of divination magic. (and therefore at higher level this plays in to the resource management game. IE: talk to the sage, research in town, cast spells, etc)
    2. If it should be OBVIOUS then you may not need a clue. Check the fucking treasure chest
  2. "Hidden" hallway traps generally suck. They slow down the game. They also push back on exploration. "Every 20 minutes take some random damage!
  3. Traps trigger infrequently. IE: on a 1-2 on a d6.
2. Someone write something once about hallway traps being good. I need to find that article

2. Is there some relationship between hidden "Take Damage!" traps and wandering monster chances? It seems unlikely because you have more options with monsters (fight, negotiate, flee) than you do with "hidden" hallway traps? But, it's also a control mechanism, it's a timer that, again, forces resource expenditure, in the form of HP & healing. But it seems different, maybe given the critical nature of HP. Riffing "combat as a fail state", the Fail State seems unfair in this case? Or maybe, the path to the fail state?

3. Whats the point of this? A pushback on dungeon certainty? IE: keep the players guessing and there WAS a hallway trap, that they hit when fleeing, after all! (uncertainty being a KEY exploration attribute) Further, is this for hallway traps or for ALL traps, including chest ones? Some part of this feels more pedantic than other arguments. It might be nice to understand the point but note it's not as important as other aspects?

Gus L.

A FreshHell to Contend With
I'm okay with hidden hallway traps - but... only when it's totally obvious the area is likely to be traped e.g. It's the secret entrance to a well guarded location or there's a sign with a skull and crossbones at the cave entrance. I also limit them to simple ones - pits covered in leaves, spears that stab from the walls and tripwires attached to grenades, but again it's like there's been a sign says "THIS IZ SNEAKY BASTARDO'S TERRITORY - YOU GONNA DIE!" or "Bomb Loving Undead Revolutionary Army - Victory Through Indiscriminate Murder!" etc. These are clumsy examples - but of course the hall to the King's Treasury is trapped - spatial reasoning is a type of sign. So yeah some fairness, but I'm pretty much okay dropping a giant rock on PCs that don't look for clues.


Should be playing D&D instead
What follows are my 2 cents on traps and riddles.

A while ago I hosted a little workshop about dungeon design on a local convention and of course traps (and riddles) were a part of that too.

In this workshop I defined some basic parts of the dungeon to get everyone in the audience on the same page.
Inhabitants were defined as
1. being mobile (they can move around the dungeon)
2. having goals ( they want stuff (food, safety, hope, prosperity,...) and act to get it)

Most design goals for a good monsters/npcs follow directly from these two points.
Mobility gives you:
- Random Encounters
- a vibrant and lively dungeon (Inhabitants move around)
- possible reactions the the partys actions (as inhabitants can move to check stuff out)

Goals give you:
- Faction play (as different inhabitants have different goals)
- a vibrant and lively dungeon (as inhabitants do stuff that makes sense)
- morals and monster reactions (as inhabitants think about their goals before mindlessly attacking the party)
- social play (as the party can negotiate or even ally themselves with inhabitants)

Why do I post all this in a thread about traps?
Because I later defined traps (and riddles) in opposition to inhabitants.
So while inhabitants are mobile and have goals (act), traps are immobile and only react.
Yet, this definition would also include sticks, stones and damn near everything that lies around in a dungeon.
A third point was needed: Traps/Riddles protect something

So now we have a passable definition of traps/riddles: They are immobile, only react and protect something.

I lump traps and riddles together here because from my point of view, they are nearly the same thing. Both are immoblie, only react and protect something (a person, a room, an item,...) ... the only difference between a trap and a riddle is how they protect something.

Traps act as barriers for the party to prevent access to whatever is protected. They either stop them long enough, kill them or weaken them enough for other security measures (guards, monsters, other traps,...) to finish the job.

Riddles act as filters. They test if the party is worth access to whatever is protected by presenting a test of some ability (intelligence most often, but dexterity, honor, nearly every trait or ability can be tested).

Good design goals for traps/riddles follow this definition as above.
Immobility gives you a definite location, while protection tells you where this location would be most sensible. It follows from the fact that traps only react, that characters can interact with them in a logical way. So from this you get to effect (what it does) and workings (how it does it) of the trap. From there one goes to how the trap is triggered, which directly tells you how it can be disarmed.
Lastly from location and function one can infer the ways the party can spot or find the trap (clues, searches, ...).

All of the above concerns mostly the InGame part of trap creation and placement of course.
You then have to take the OffGame reason to place a trap (draining ressources, challening players, creating tension, ...) and matters of fairness (player agency) into the equation.
A efficient and good trap designed after my definiton above would always kill the party without giving them much chance to act. That of course is the InGame goal of everyone who places a trap (most times at least. I can think of some situations where a trap is placed for other reasons).
By taking the OffGame reasons into account you can then temper that extrem into something more enjoyable for all at the table.
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So ... slow work day? Every day?
I've been thinking about traps lately because they are difficult for me to think up news ones besides a pit, and I had a few adventure locations that I felt needed some—a ‘trap’ dungeon in Trollback Keep, and a thieves’ guild “dungeon” in my City of Vermilion for my patreon.

I don’t like using hidden, random hallway traps—what a pain for the current residents? It doesn’t make sense if its in a well traveled hallway. But kobolds and whatnot usually have hidden pit traps in their passages—but that should still provide clues (place is dusty except for a narrow trail hugging the west wall, etc.). If I lived in a cave...I would have some traps created, but I'm paranoid.

The points made above (slows down play, etc.) is all true, but what is the point of hidden hallway traps? I think its an effort to tap into the resource game and have players make decisions---how it affects encumbrance and spells chosen. When’s the last time a player bought a 10’ pole for their character in your group? I’m thinking its been about 10 years for the group I’m with...granted, we are a bit slow in the head, but mainly because we use encumbrance and we are always skimping on things because armor is freaking heavy. Our marching order gets spread out too, depending on who is carrying that 10’ pole, and movement can become a pain.

Is this why thieves are not very popular (they are one of my favorites btw)? They slow down the whole group...the player may care about their characters life, and yet they are the ones expected to search ahead, taking risks. If hidden hallway traps are really slowing down play, the cleric can cast Find Traps—again, making the character choose their resources. In hindsight, thieves should maybe get a passive Detect Trap skill, like elves do with secret doors. It gives them that 6th sense feel that something isn't quite right and then they could look for a trap..this might speed up play. And it might be cool for other party members to be able to be more involved with disarming traps somehow—which could be the case depending on the trap—but it would create more interaction for everyone then just the thief.

I think traps on chests are too obvious...and gets old...and yes, I still do them. It's almost expected though. Ahh...a chest? Ok, I search for traps. And the part that sucks about that is it takes away something that traps can bring to the table. That sense of danger, stress, or pressure. Unfortunately, hidden hallway traps take that away as well and becomes more of a 'gotcha' moment which can get lame, so I agree that hints and clues to a trap can be important.

Not sure I really had a point to all this, but as I was writing this, I may play with the idea of adding a "trap noise" to the wandering encounter table. If you roll it, the DM can explain the sounds of rumbling or interlocking gears moving--but nothing happens. Maybe the trap is too rusty or is broken—it doesn’t matter...the description of the sounds would provide tension and feeling of danger that I think is neat during play, while not giving that 'gotcha' feel when you take damage.


i fucking hate writing ...
Staff member
Hmmm, it you take Mobile & Goal, Active & Reactive, and put them in a four-square grid ... then you get Mobile/Active as monsters and Immobile/Reactive as traps then what goes in the other two squares, @Grützi ?

@Malrex , I had a couple of thoughts about your post.
  1. The "slow dungeon explore speed" has, I assumed, a 10' pole "trigger traps" built in? I usually give is a 1-2/6 if the party has poles, or more depending on circumstances. Am I the only one?
  2. Riffing on the 10' pole and your statement, a Thief abstraction mechanism could make them less odious. Once Find Traps, Divinations start to show I usually get more merciless with the traps. Few to no hints, more deadly effects. That forces a cleric in resource spells and away from heals/combat in the same way a MU is with knock/comprehend/fireball.
  3. The chest obviousness is interesting. I have always seen certain "gotcha!" stuff as a reaction to that. The ear seeker, mimic, yellow mold, gCube. These seem to be a reaction to the players "de rigueur" actions. Once it becomes obvious, you twist it a little. Which forces more "resource" spells from the party, etc. An arms race, done fairly by the DM?
I wonder, if the "search for traps roll", and therefore thief, bypasses a lot? The interactivity between player and DM is lessened by a "I roll for it." Whereas if everyone is a thief and you interact then "the clasp is in the shape of a mouth" "i look inside the mouth for a trap" "you see a needle" is lost?


So ... slow work day? Every day?
1. I really like your 1-2/6 rule for traps (is that from Basic?--been awhile...). But I comprehended that differently. I would of used that rule as does the trap actually go off? My logic is that traps can be crude and its medieval times so things don't necessarily work perfectly--but this is different and may be automatic if its a glyph or something magical. Stealing the idea.

2. I think there is a fine line between more merciless with traps with less hints and rewarding the players for using spells/resources to find a trap. I think you are doing it right as encouraging players to really think about their spells/resources I think is a good thing and brings more variety to the game. My group--usually its damaging or healing spells (which is too bad), but I think we are more of a battle intensive group.

3. You can twist ideas for a chest...but its still "the chest"...which makes most players believe something will be off about it. So yes, they might expend different resources and you can play the arms race game, but since its such an obvious place for a trap--the trap loses it's power of the unknown or surprise factor--which I think is too bad. I never remember what type of trap was on a chest (ok, poison needle, just like 90% of chest traps)--easily forgettable experience...but we still talk about the "sloping passage with boulder rumbling towards us and pit trap"--because it surprised us, it gave us that sense of terror--'something is rumbling towards you and a huge boulder shakes the hallway as it bounces towards you at high speed' and it was funny because one guy actually tried to use the guy that fell in the pit as a springboard to not fall in the pit and avoid the boulder that was right behind him.

4.I think it depends on when you have the thief roll their Find Traps. So this is easy for chests--player usually says 'ok, I search for traps'. Depending on DM style, this is when you can hold off on the Find Traps roll and do the interaction and have the back and forth of what the character is doing and the DM telling them what they see--then at some point they roll to see if they Find the Trap.

For hidden hallway traps, from this discussion and thinking about it, I may adopt the 1-2/6 rule for thieves or people with 10' poles or other cautious actions--just like elves get for secret doors. That 1-2 gives a '6th sense' vibe to a thief. If coming upon a trap, I would roll for the thief and just say 'something feels off...' then we can have interaction if they search for a trap, etc. But also thinking about it...people using 10' poles may make a continuous scraping noise or echoes of poking... which may increase wandering encounters chance....


Should be playing D&D instead
Hell if I know. I mean you and the others are the old masters ... I'm just some noob from germany :p

But seriously, I never really tought about it that way. Let's see.
Some Monsters/npcs could be immobile and still act in some capacity. A friend of mine likes to place intelligent lakes in his games .. stuff like that.
Also there are trapped or bound monsters ... but that last one really feels like moving the goalpost ... I mean, a trapped monster is basically mobile/active, just on a smaller scale.

I will go with natural phenomena here. Weather, water, wind, magic storms ... such stuff. They clearly move around, yet have no will or goals of their own. A slowly flooding dungeon, a freak thunderstorm, a magic effect gone haywire ... such stuff.

So we get something like this:
Active (acts)Inactive (reacts)
MobileMonsters/Npcsweather and nature effects
Immobiletrapped or bound monsters/npcsTraps and Riddles

Then again the whole definition thing was never a clear and perfect, two option (Active/Inactive; Mobile/Immobile) fit ... I had to put in another point (protects something) for traps/riddles to make it work.

For me the important part was the active/inactive distinction. Does something have intelligence, a will and goals of its own and a means to achieve them? Then it's active, if not it's inactive.

For Clarification:
When I write or plan a dungeon I break the parts down into four broad categories:
- History (inward history, outward history and meta-history of the dungeon)
- Layout (map, rooms, architecture, materials,...)
- Inhabitants (monsters, npcs)
- Interactivity (Loot/Treasure/Ressources, Traps/Riddles, Weather/Surroundings/Dungeon itself, Curious stuff)

This breakdown is by no means absolute, there is a lot blurring the lines going on here, but it helps me get my shit together ;)

Inhabitants are basically another part of interactivity in that you can interact with them in meaningful ways, but they are active, while the rest is inactive or passive so thats where I draw the line ;)
Like I said a lot of blurry areas here ... is an intelligent sword an inhabitant or simple loot? Is a statue that tells you the secrets o the dungeon?
Depending on your point of view you can propably drive a semi trough the holes in my little model here :)
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Should be playing D&D instead
Nice matrix, Pseudo.

But honestly, y'all are kinda overthinking all of this. Traps are easy. They're not like writing riddles or designing unique encounters or anything.

With a trap, all you need is something to happen to the players (type of damage/effect) - the rest is dressing. The trigger, the plausibility, the warning... extra shit. The only real hard part is coming up with a cool effect.

The trigger is just "what do you want to be trapped? Ok, when they try to use/bypass/enter/etc it, then the trap springs. Door opens - trap sprung. Floor stepped on - trap sprung. Glass orb fucked with - trap sprung.

Then its just natural progression into the "how?" of it all. How does opening a door drop a giant boulder? Cantilevers. How does lifting a gem off a pedestal release a swarm of spiders? Pressure plate. How does drinking from a fountain mutate a person? It's got a bunch of glowing shit floating in it. Etc.

The effect of the trap dictates the warning. Acid effect? Noticeable smell, empty vial with residue, melted corpse, corrosion on the lock, etc. Portcullis drops down to split the group? Holes where it drops down, physical tripwire, little hieroglyph showing a spiked gate dropping onto a man, etc.

The plausibility of traps simply comes down to the trap's location. You just think "if I built this place, where would I place a trap that protects my shit and doesn't fuck with my minions?". The questions like "how does it reset?" and "why would they trap a common staircase?" or whatever are inconsequential - players honestly don't give as much of a fuck as designers seem to think they will. Even if you're worried about it, it's always a super easy solve (magic exists, remember?).

Again, the hard part is thinking up stuff that's much cooler than the old "spears thrust out of the wall" or "scythe cuts across the hallway". You want something like a giant spectral hand that pulls a soul out of a person, or a fountain that starts gushing out an ooze. Once you have that, the rest is dressing.


8, 8, I forget what is for
Late to the party, I know, but I didn’t have time to write a decent response.

In my game, out-of-game, hallway traps have two functions:

1. The primary function is to be an obstacle/challenge to overcome.

2. The secondary function is to add a level of risk and uncertainty to running away and certain fear based effects.

Because of function #1, during ordinary exploration, traps are more interesting if they are discovered than if they are not discovered. An undiscovered trap is just the application of random damage or death. A discovered trap is a full blown puzzle/obstacle encounter.

For this reason, I make hallway traps automatically detected using ordinary, prudent dungeon exploration procedures like use of a 10’ pole. However, detecting the trap does not mean understanding the nature or operation of the trap: that comes out of play.

Chest/door traps serve a different function. Since they are in a location where players anticipate there might be a trap, it is OK if they are not found. If a trap is not found, the players can’t be sure there isn’t a trap anyway, and they have a choice to make regarding whether to open it now or later or not at all, and what precautions to take (some of which might damage the loot inside a chest, or break a door you really which you could close and hold later). If the trap is found, then is it turns into a puzzle encounter as the PCs try to discovery the nature of the trap and circumvent it. Courtney has a brilliant series on this in his trick and trap index.

Room can be treated as hallway traps, but I prefer to turn them into chest/door traps by including some sort of readily detectable clue, however small – like holes or striations on the wall, or a tile pattern that might conceal pressure plates, or a smear of blood, or scorch marks, or a corpse. In order to also create uncertainty as to whether there is a trap, this means I also need to have a few otherwise empty rooms that have something that might be evidence of a trap but are actually red herrings.
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