This month we have a guest post from Alexander Atoz of dragonencounters.com.
Traps are probably the second most iconic feature of RPG dungeons—right after monsters. And yet, despite their reputation, they’re often the most poorly used. Many RPG rulebooks suggest resolving traps through a simple dice roll or a skill check. Instead of a challenge, it’s a coin toss – taking something that should be interesting and exciting and turning it into a random punishment for bad luck.
Even when traps rely on player decisions, those decisions tend to be blind guesses—Which lever should we pull? Should we open the chest? Lacking real information, these moments might as well be random.
It doesn’t have to be that way.
Traps have enormous potential to create memorable moments and challenge players in creative ways. Used well, they can transform exploration into intense puzzles, force clever problem-solving under pressure, and even shape the very character of a dungeon.
In this article, we’ll explore several ways to make traps a meaningful and rewarding part of your adventures.
How to Design Hidden Traps
In the matter of detecting traps, one of the simplest solutions is to make them rely on logical clues players can observe, rather than just rolling dice. Trap builders need to avoid their own traps, so subtle markers often exist—if the players are sharp enough to spot them. However, these clues shouldn’t be obvious.
The trick is to conceal the clues just enough that the players have to be paying attention. Here are some methods to do so.
Subtle Markings: Add small descriptions to the areas where the traps are. Broken tiles, gouges left by swords (or holes left by bullets), and spots of paint that look like bloodstains are just noticeable enough for a GM to describe, but also possible to dismiss as unimportant.
Logical Areas: Tie the clues to the dungeon’s inhabitants. Dwarves wouldn’t use high levers—perhaps only those trigger traps. Sentient spiders don’t need stairs, so maybe those have been booby-trapped.
Environmental Cues: Combine creature logic with environmental details. The effects of a monster’s presence may mark the safe or dangerous areas. A wide, clear hallway might warn of something too large to navigate tight spaces. A spotless floor could hint that a creature leaving slime or fur never passes through.
With this approach, distraction isn’t just helpful—it’s necessary. Players will pick up on small details like a clean floor or a scattering of insects all too quickly if such descriptions stand out.
To hide the clues in plain sight, you need to surround them with other details worth mentioning. Describe the faded murals, the broken furniture, the lingering scent of smoke—anything that lets you naturally repeat and reinforce environmental details without drawing undue attention to the important ones.
Misdirection: A similar, but different, approach. Instead of hiding it behind hard-to-notice details, provide a lot of different details. For example, provide series of murals along the length of a wall. Even after finding out that the cherry tree and watermelon mark traps, can they figure out that there’s a pattern. If they do, is the trigger plants, food, colors, or simply every third tile?
However you hide them, spotting traps is hard, so balance the challenge by keeping the damage low when they fail.
Combining Narrative Clues With Game Mechanics
One challenge with using trap clue mechanics is that they can seem to sideline certain character abilities. In many TTRPGs, some classes or characters specialize in detecting and disarming traps. If everything comes down to player observation, those mechanical advantages risk becoming irrelevant.
Fortunately, it’s easy to combine narrative clue-based traps with the traditional search mechanics to keep both player skill and character skill relevant.
Most TTRPGs don’t clearly define how long a search for traps takes. If your players are under any kind of time pressure—whether they’re trying to achieve surprise, rescue hostages, interrupt a ritual, or prevent enemies from escaping—they simply don’t have the luxury of inspecting every inch of a dungeon. Instead, they’ll need to pay attention to narrative clues to decide where to search, and rely on their character’s abilities to improve their chances when they do.
Strong search skills can also help mitigate failure. Even when players misinterpret the clues or miss a hidden danger, a successful roll might reduce the consequences—allowing them to avoid the worst of the damage or disarm part of the trap before it fully triggers.
How to Construct Mysterious Traps
A different style of trap focuses less on discovery and more on solving a mystery that’s right in front of the players. In this case, the trap’s presence—and often even its location—is obvious, but the danger lies in figuring out exactly how it works to avoid triggering it.
Statues are a classic example. Everyone knows that if there’s a statue in a dungeon, it’s probably trapped—but how? Figuring it out forces players to carefully prod the statue, study the surroundings, and work through the possibilities before acting.
For a more advanced version, layer in misleading clues or combine multiple traps. A statue holding a gem might have small openings suggesting fire or darts could shoot out, leading the players to crouch low to avoid the danger. But in doing so, they shift the statue’s already-unstable balance, causing it to fall and shatter—releasing poison gas into the room.
You can also create mechanical puzzles with hidden consequences. Imagine a bag tied to a rope hanging from the ceiling. The rope runs up past a chandelier and disappears into the rafters. Unseen, the other end of the rope holds up the chandelier itself. As long as the bag stays in place, the system remains balanced. But remove the bag’s weight, and the chandelier crashes down—perhaps sending shards of glass flying, or even starting a fire.
Even disarming traps can present this kind of layered challenge. Jumping over a pit trap might lead a character to land directly on a hidden tripwire. Cutting a tripwire could disable the trap—or trigger it. And even if the PC is wise enough not to stand in front of a suspected arrow trap, they might not realize that a cabinet full of glass bottles sits directly behind it. One wrong move, and the bottles shatter—either sounding an alarm or releasing poison gas.
Combining With Game Mechanics
For mysterious traps, game mechanics work best as a way to reveal additional clues rather than to bypass the puzzle entirely. A successful investigation check might reveal that the vents in a statue are clean—suggesting they’ve never been fired—or that faint scratch marks near the statue’s base hint at a different danger.
Players with high relevant stats should naturally uncover more detailed information when examining key elements. For instance, if a character with sharp perception or technical skills inspects the chandelier, you might mention that it sways slightly or that the rope shows signs of recent strain—clues you wouldn’t offer to a less observant character.
Don’t tell him that his character notices it as that will give it all away. Provide the information to everyone equally, but only if that character is the one looking.
When it comes to disarming the trap, the mechanics become even more obvious and valuable. Once the players think they’ve figured out how the trap works, this is the moment for the character with steady hands and practiced skill to shine—cutting the right wire, wedging the right mechanism, or disabling the trigger with practiced finesse.
How to Devise Manipulative Traps
The final category of traps isn’t about hidden mechanisms or complex puzzles—it’s about reading people. These are traps that players detect not through careful observation of the environment, but by recognizing the intentions and behavior of the person who set them.
A simple example is a treasure—a large, valuable gem—left out in plain sight, completely unsecured. No one would be foolish enough to leave it there, so it must be a trap. Similarly, if the villain offers the players food or drink, it’s only logical to assume it’s poisoned.
On a more subtle level, anything out of character should raise suspicion. Just be sure you’ve established the villain’s typical behavior before using this kind of misdirection, or the players won’t have a fair chance to catch the inconsistency.
Where this becomes more interesting is when the villain deliberately plays on the players’ expectations. Perhaps the villain tells them the passage they seek can be unlocked with a certain lever. Do they believe him—or do they make him pull the lever first? But maybe that’s exactly what he expected. Pulling the lever himself keeps him standing safely on the one spot that isn’t electrified when the trap triggers.
Sometimes, the villain’s behavior is warning enough. If he fires at them from the far end of a hallway but never advances, that might suggest the hallway is rigged. My players once figured out a boulder trap simply because the hallway ahead was narrow, had rounded edges, and sloped gently upward.
[As an aside, they were supposed to go up it—I had set an ‘avoid the trigger’ trap further along. Instead, they refused to enter, completely derailing the plan. My fault entirely.]
Manipulative traps work best when they encourage players to question their assumptions and debate their choices—adding tension even before any dice are rolled.
Signaling the Presence of Traps
A major challenge in running a trap-heavy dungeon is ensuring players actually realize traps are present. After all, they can’t try to avoid or disarm traps if they don’t know to look for them.
There are several ways to handle this:
Let Them Learn the Hard Way: Sometimes, the simplest solution is to let the players stumble into a trap or two. If the traps only deal moderate damage, this serves as an early warning without feeling unfair. This approach works best when traps are hidden behind clues the players can piece together after the fact.
To prevent players from simply absorbing trap damage and moving on, raise the stakes as they progress. Perhaps the villain saves his deadliest poisons for traps guarding more sensitive areas. You can also introduce debuffs—early traps might impose minor penalties that don’t matter much without enemies around, but later traps apply their effects just as enemies begin to appear.
Make Traps a Set Piece: When traps require active problem-solving, place them in special locations—guarding treasure, blocking passage, or situated in clearly significant rooms. The sight of ropes, mechanisms, or suspiciously placed objects can tip players off without directly telling them a trap is present.
Foreshadow Danger: Build tension through narrative hints. The quest giver might warn them of a trapped lair, or they might stumble across the remains of a less fortunate adventurer, killed by a trap. And where there’s one trap… there’s probably more.
Keep Your Traps Thematic
Resist the temptation to fill a dungeon with many different types of traps. Especially in classic designs, less really is more.
Using a single type of trap throughout a dungeon has powerful advantages. It creates a clear pattern that players can learn from and anticipate, turning the dungeon itself into a kind of logic puzzle. Instead of constantly wondering if there’s a trap, players focus on figuring out where and how it’s hidden.
For example, if players realize the dungeon is filled with pit traps, every open space becomes suspicious. If it’s crossbow traps, they’ll start scanning for suspicious holes in the walls. This keeps them engaged and rewards careful observation—without overwhelming them with a jumble of disconnected hazards.
The main exception to this is with mechanical traps, where some variation may be necessary to keep players guessing. Even then, limiting yourself to a single type of trap with different triggers—such as multiple ways to activate the same deadly mechanism—can create a rich and cohesive challenge, without sacrificing variety.
Remember: the best trap isn’t the one the players don’t see—it’s the one they see coming and have to figure out how to avoid.
About the Guest Author – Alexander Atoz
I grew up building RPG type games for my brothers, (mostly my own systems). As an “adult”, I’m building RPG scenarios for anybody interested online instead. My main work is on my blog, dragonencounters.com where I’m building scenarios for every single D&D monster in the manual, in order. (I’ve alreay done all forty dragons.)
Read more at this site