Traps are kind of an unsolved problem in 5e D&D (of course, I said this before about 4e). On the one hand, you can’t leave traps out, because they’re an integral part of the dungeon delver fantasy. On the other hand, the way they’re usually used in 5e is not fun. Your stock 10-foot-pit trap is (if your passive Perception is high enough) a piece of scenery hardly worth mentioning, or (if your passive Perception is low) an unavoidable hit point tax, or (if your DM doesn’t use Perception) a guess-what-the-DM-is-thinking game, or (if overused) an incentive to play in a laborious and dull style involving ten foot poles.

Even the writers of 5e don’t have a lot of faith in traps. Consider their advice from Xanathar’s Guide:

If your encounters or adventures are sown with too many traps, and if the characters are victimized over and over again as a result, they are likely to take steps to prevent further bad things from happening. Because of their recent experience, the characters can become overly cautious, and you run the risk of the action grinding to a halt. Traps are most effective when their presence comes as a surprise, not when they appear so often that the characters spend all their effort watching out for the next one.

I think this is wrong. Call me naive, but I think traps can be fun. Don’t be stingy. Slather them on! Run an all-trap dungeon. Run an all-trap adventure! If you’re willing to put a little extra work into it, there are ways to make each trap into an entertaining encounter.

I’ve been the victim of many traps in my years of playing D&D (and also inflicted a few as the DM). Sometimes, defeating a trap can feel extremely satisfying, and even falling victim to a trap can be a hilarious table moment. It all comes down to warning the players, implicitly or explicitly, that they might be walking into danger.

Here are the setups of some of the traps I’ve enjoyed most as a D&D player. We’ll get into the trap solutions later on.

In the dungeon corridor ahead, a glowing dagger floats in the air.

A glass tube extends from the floor to the ceiling. Inside the tube is a statue holding an apparently magic weapon.

A room contains 4 rotting sofas, several throne-like chairs, vases, and urns which are dented, chipped and broken, stands, small tables, and braziers, all jumbled together.

player skill vs character skill

The traditional trap dichotomy is between old school “player skill” style and new school “character skill” style.

The “player skill” school holds that characters should perform certain intelligent actions to avoid traps – prod every floor with a pole, throw a coin onto the metal floor, pull the lever with Mage Hand while standing across the room.

The “character skill” style relies on die rolls. Your characters are more competent adventurers than you are – a character with high Perception shouldn’t miss an obvious trap because their player didn’t guess what action the DM expected them to take.

In most D&D situations, player skill vs. character skill is a false dichotomy. If you want to get up a cliff, you can either use an Athletics check or do something clever with ropes. If you want to convince a guard to let you pass, you can make a Persuasion check or you can say something reasonable. There are many solutions to any problem.

Traps don’t have multiple solutions because they often don’t present themselves as problems – by the time you know there’s a trap, the encounter is over. Traps exist outside the usual D&D action loop, which is described in the PHB as:

1. The DM describes the environment
2. The players describe what they want to do
3. The DM narrates the results of the adventurers’ actions

The trap action loop is more like this:

1. The players blunder without warning into a trapped area
2. The DM compares passive perception to static DCs and describes the PCs avoiding or triggering the trap
3. the players write down damage on their character sheet, or take some trivial action like walking around a pit or stepping over a tripwire

That’s why the trap-sprung-without-warning doesn’t work very well. When you remove the player’s ability to react to a situation, D&D becomes a game about comparing passive DCs or about performing methodical danger-avoidance routines – and the game begins to fall apart.

Traps work best when they’re telegraphed.

The odd detail

Remember the list of my favorite trap setups I gave above? The common thread: they all include an odd or mysterious element that invites exploration.

The odd detail can be an obvious clue to the nature of the trap – rubble on the floor below a collapsing ceiling trap, or a dead thief near a poison needle trap – but it can also just be a specific detail that cries out for investigation: a chalked arrow on the floor, or a door painted with a woodland scene. It doesn’t matter much what the detail is, just so it stands out enough to attract the players’ interest.

It might seem like telegraphing every trap makes it too easy on the players. After all, players can just choose to ignore or steer around anything with a suspiciously lush description. Not to worry! Odd details are like catnip to D&D players. Characters come from miles around to stick their heads in the sphere of annihilation trap.

The odd detail is the missing piece of D&D traps because it indicates to the players that there’s something to actively investigate. Without it, traps are just something DMs inflict on characters. You’d much rather have traps be something the characters inflict on themselves!

investigating traps

How do characters deal with traps? Once you’ve indicated that there’s something that may be worth investigating, the players can choose their own course of action. All the DM has to do is react. This brings traps back into the classic D&D paradigm from the PHB: the DM describing a scene, the players stating their actions, and the DM adjudicating the results. As an added benefit, players can organically choose between using old-school player skill and modern character skill, just as they can in other open-ended D&D scenes.

Given a suspiciously odd detail, players will generally act in one of three ways:

call for a general perception check. “I examine the lacquered cabinet and its surroundings,” or just, “I make a perception check.” The player is choosing to use character skill, not player skill, here, and that’s fine. On a success, the player spots the trap trigger but doesn’t necessarily learn how to disarm it, or even what it does (though it may be obvious.) On a perception roll failure, the character has to try something else. Note: if several characters make nonspecific perception checks, use the rules for group checks! Otherwise, success is all but assured in the most boring way possible.

examine something specific, or ask a specific question. “Does the cabinet seem to be locked or sealed in any way?” I tend to reward specific inquiries with automatic success. “No, there’s no lock on the cabinet.” If the player wants to engage the trap using their player skill, I want to honor that choice by putting away the dice.

blunder forward because they weren’t paying attention to the DM’s hints. In his article The Flow of Trap Detection, Sly Flourish notes that half the time, D&D players aren’t understanding the DM’s description. That’s such an important point that it should be printed on DM screens. Let’s call it “Sly’s Law of Comprehension.” Frequent misunderstanding is a fundamental part of the medium, and usually neither the player’s nor the DM’s fault.

So when a player inevitably misses a hint and walks into a trap, does that mean that they deserve to be spanked with inevitable trap damage? No! Here’s where passive perception finally comes into play. If the character ignores hints and blunders towards a carefully-clued trap, the DM can use their passive Perception to give the character a chance to spot the trap trigger.

countermeasures

Once players are aware that they may be in the presence of a trap, they have two choices.

Make a skill check to disable the trap. This is putting their character’s survival in their character’s hands. It’s probably the most common approach in 5e, and it’s probably the safest as well.

take a specific action which seems logical to them at the time. Players can use their “player skill” to take methodical, brilliant, or wildly ill-considered actions. Such actions should usually either succeed or fail depending on what seems logical given the trap setup. No die roll is required. If Chewbacca chooses to grab the suspicious trap bait hanging from the tree, he ends up triggering the net trap. (He still gets a saving throw, though.) If Indiana Jones throws sand on the invisible bridge, he, or anyone else, can cross it without making a Perception check or taking a leap of faith.

Sometimes, the DM’s “odd detail” will clue players in to act cautiously. Other times, the details will act like bait, suckering them into dangerous actions. And that’s OK too. It can be fun to disarm a trap with your brain, and sometimes it can be just as much fun to disarm it with your face. Everything’s better when you have agency.

What I’m suggesting involves work for the DM. Basically, every trap becomes a micro-puzzle. D&D is flexible: players who don’t relish puzzle-solving can roll a few dice to have their characters solve it. But whether the players take a new-school or old-school approach, every trap is the better for a few memorable, specific details.

trap solutions

Here are the “puzzle solutions” to the traps I mentioned at the top of the page.

“In the dungeon corridor ahead, a glowing dagger floats in the air.” This happened in Mike Mornard’s game. My thief heedlessly reached out to grab the dagger and ran into a gelatinous cube. I felt that the encounter was fair because I inflicted danger on myself by acting incautiously. If there had been no floating dagger, no clue to the gelatinous cube’s presence, it would have just felt like DM fiat.

“A glass tube extends from the floor to the ceiling. Inside the tube is a statue holding an apparently magic weapon.” My buddy John ran this as part of an all-trap dungeon, a museum where the traps themselves were the exhibits. Most were from Grimtooth’s Traps.

In this trap, the glass tube is filled with poison gas: break the glass and get a faceful of poison. I suspected something of the kind, so we summoned some kind of canary-like creature into the tube to prove that it was poison, and then broke the glass and grabbed the treasure from afar. Mage Hand was involved, I believe. We had a blast and felt really smart solving this one.

“A room contains 4 rotting sofas, several throne-like chairs, vases, and urns which are dented, chipped and broken, stands, small tables, and braziers, all jumbled together.” This one is from the original Tomb of Horrors, which has some unfair traps, but this, I think, is a fair one. After a few minutes in the room, the floor will start to jump and buck around, tossing the furniture and characters wildly, and inflicting minor damage on the characters. The Pop-O-Matic action of the trap is a great explanation for the bizarre state of the room.

training your players

Players need to learn that every trap will be marked with a clue. No matter how many traps you spring, that will prevent them from wasting their time searching barren rooms for traps. “You’re in a ten by ten room. Door to the left, door to the right.” There must NEVER be a trap in a room described like this! There’s nothing interesting or off-beat that signals that this is an investigation scene.

Players also need to learn that there can be benefits from interacting with weird elements in your dungeon. Otherwise, every suspicious scratch on the floor will make your players run the other way. Luckily, D&D has a strong built-in slot-machine-like reward system. Treasure! In standard 5e D&D, about 1 in 5 monster encounters come with a treasure hoard, and lots more carry some incidental treasure. Treat traps just like any other encounter. It’s easy to litter treasure around a trap:

The trap was set up to guard the treasure! Guarding valuebles is, after all, one of the most likely uses for a trap.

A previous victim of the trap has a sack full of treasure! Nothing says “search this area carefully” like a dead thief.

The treasure is the trap’s bait! The “odd detail” is the treasure itself, clearly in sight, although all is not as it seems.

traps in the Inspiration app

Of course, my Inspiration app is chock-full of traps. I’ve got something like 80 trap types, from the basic pit trap to the rolling boulder to the demon-possessed item, and each trap is further detailed with 3 or so “odd details”. That’s something like 250 unique traps. None of them are very complex, but I hope they’re just puzzling enough to give your players a moment of uncertainty.

Here’s how I construct the traps, and here are some samples for use at your table today.

trap template

I use a modified version of the trap template presented in Xanathar’s Guide.

Trap Name: The best trap names end in “OF DEATH”, but I leave the prefix up to you.
Challenge Rating: D&D 5e traps don’t have a challenge rating; instead they have a level band, like 1-4, and a degree of severity, like “moderate” or “deadly.” I think this is a mistake. It’s insufficiently granular – even a moderate level 1-4 trap will probably kill a first-level character – plus challenge rating is a tool we already have from monster design! Combining trap recommendations plus my 5e Monster Manual on a business card math, we come out with the formula that a single-character trap should do about 5 damage per CR, while a multi-character trap should do about 3 damage per CR.
Description: A sentence to sum up the trap.
Clues: This is where you put the odd detail that will get the characters’ attention. No trap is complete without one! In my case, to increase the usefulness of each trap in the Inspiration app, I’m providing three possible clues per trap. I hope that this will make the same pit trap feel different if encountered again.
Investigation: What can the characters learn by investigating the trap? I try to include both normal search check results (what the characters learn with a Perception check) and specific, guaranteed-to-succeed actions that will automatically net a clue.
Trigger: What action causes the trap to go off.
Effect: What happens when the trap is triggered.
Countermeasures: What actions the players can take to avoid or disarm the trap. Again, when I can I include both skill checks that will disarm the trap and specific actions that will automatically defeat it.

Here are two examples:

Name: 30-foot-deep locking spiked pit trap
Challenge: 6
Description: This 30-foot-deep pit has a cover which snaps shut to seal its victim inside. It has wood or metal spikes on the bottom.
Clues: A trail of faint footprints abruptly end. (DM note: In this case, there is a corpse in the pit.) OR: an arrow is scrawled in chalk on the floor. (DM note: The arrow points to the pit. It was drawn by a denizen who was worried about forgetting where it was and falling in.) OR: The center of the room is dusty; the floor at the edges of the room is clean. (DM note: The clean area is well-traveled and safe to traverse.)
Investigation: A DC 14 Perception check reveals that foot traffic avoids the pit cover. A DC 14 Investigation check reveals the hidden pit trap. A DC 19 Investigation check not only reveals the pit trap, but discovers a hidden lever, loose brick, or catch which opens the pit lid. A character who taps the floor notices that it sounds hollow.
Trigger: A creature steps on the trap cover.
Effect: The trap cover swings open like a trap door, or swings on a pivot. The victim falls into the pit, taking 10 (3d6) falling damage and 11 (2d10) piercing damage from spikes. The spring-loaded (or weighted) cover then swings shut and locks. The cover can be opened with a DC 18 Strength check; from inside, with a DC 16 Dexterity check using thieves tools, assuming there is sufficient light; by breaking the cover, which has AC 20 and 20 hit points; and sometimes by finding a hidden lever which opens the pit.
Countermeasures: Once the pit is detected, an iron spike or similar object can be wedged under the cover to prevent it from opening, or it can be magically held shut with Arcane Lock. Or you can walk around.

Name: ice-breather trap
Challenge: 12
Description: This trap breathes a blast of cold whenever someone speaks the word “ice”.
Clues: The room is cold. A ten-foot-tall statue of a barbarian or frost giant dominates the room. The statue appears to be made of ice. (DM note: The ice is magical and does not melt.) OR: The room is cold. There’s a carving of a polar bear on the wall. On the bear’s head is a rune. (DM note: The rune says “ice” in Giant.) OR: The room is cold and contains a marble statue of a fur-clad elf. As you enter the room, a Magic Mouth spell animates the statue’s mouth: “Speak not my name at any cost: a river’s skin in the season of frost.”
Investigation: A DC 15 Perception check reveals that the mouth is nearly clogged with snowy ice crystals. A spell or other effect that can sense the presence of magic, such as Detect Magic, reveals an aura of evocation magic around the statue.
Trigger: The trap activates when someone speaks the word “ice” in Common.
Effect: The mouth releases a 30-foot cone of cold. Each creature in the blast must make a DC 17 Dexterity saving throw, taking 38 (7d10) cold damage on a failed save, or half as much damage on a successful one.
Countermeasures: Placing an obstacle in front of the mouth deflects the cold blast. A successful Dispel Magic (DC 15) cast on the mouth destroys the trap. Not saying “ice” also works.

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