As you probe deeper into the necromancer’s lair, you come across a white-and-black checkered room. Several towering chess pieces are arranged on the grid, standing at attention. After some investigation, you realize that the door ahead will open only if you push the pieces into the right configuration. Make a mistake, however, and a deadly trap will be sprung…

If you’re a fan of role-playing games, I’m sure you’ve encountered something like the above. The protagonists must solve a puzzle or a riddle in order to progress through the ancient ruin, or whatever it is they happen to be exploring. The GM’s intent is obvious—to challenge the heroes’ minds, rather than their might.

But have you ever paused to think, “Who would build such a thing, and why?”

This is one of my biggest pet peeves when I look at adventures others have designed. If I were an evil villain conducting dark experiments in my secret lair, or a mistrustful emperor looking for a place to hide my wondrous treasure, I wouldn’t construct a security system that could be bypassed by anyone who took the time to think about it carefully. I’d create something that I knew would be almost guaranteed to stop or kill all trespassers (no matter how ingenious), while letting me come and go whenever I pleased.

That being said, as a GM, I love pitting the players up against puzzles. In fact, I try to include at least one puzzle in every adventure I run. So what is a GM to do?

The easy (lazy) solution is, of course, to ask your players to suspend their disbelief. Sure, the necromancer has no good reason for protecting the entrance to his lair with a chess puzzle, but who cares? In the end, the players have a good time trying to figure it out.

But, as I mentioned in my previous tip, I try to avoid breaking immersion whenever possible. I want all parts of the setting to feel consistently realistic and believable. It might take a little extra work to design not only a puzzle that’s fun to solve, but one that makes sense, but the payoff is worth the effort.

So, without further ado, here are my tips for designing believable puzzles:

#1. Literally Anything Can Be a Puzzle

First of all, what is a puzzle? The images that probably jump into the minds of most GMs and players are that of interlocking jigsaw pieces, riddles, brain teasers, and movable blocks (a la Legend of Zelda). To design a truly interesting puzzle that feels like it belongs in the game setting, however, you’re going to have to think outside such a narrow box.

I would argue that a puzzle is any kind of mental challenge that is possible and entertaining to solve. That is, there must be at least one solution, the puzzle-solver must be aware that a solution exists, and the process of finding the solution must be a matter of critical thinking and creativity, rather than of tedious work or brute-force guessing.

So any situation that taxes the players’ mental capacities in a fair and interesting way is a puzzle. It’s quite possible that several puzzles could come and go in an adventure without the players (or even the GM) being totally aware of them as such. A trap with a hidden disarming mechanism? Puzzle. A secret door? Puzzle. A combat scenario that requires careful tactics? Puzzle. A murder mystery? Puzzle. Trying to figure out the best way through the arctic wasteland without running out of food or being attacked by dire wolves? Puzzle.

#2. Put Yourself in the Mind of the Architect

Okay, but sometimes you want to challenge your players with something more overtly puzzle-like; something that causes them to put down the dice and put on the thinking caps. There are certain players out there who get a special gleam in their eye when they see that the GM’s just dropped a puzzle in their lap, and all they need to do is figure out the answer.

This is where you need to consider the motives of whoever built the damn thing. If the architect purposefully built a solution into it, that means they wanted someone to come along and solve it. If they didn’t want that to happen, then they’d at least try to take precautions to stop potential trespassers from finding the solution.

In the same adventure I mentioned in my first GM Tip, the players found a pile of encrypted documents inside a mechanical complex. The messages were encrypted because the gnome who had written them wanted to keep notes for himself and his fellow mechanics, but he was afraid that if they fell into the wrong hands, the machines could become disastrous weapons of war. Thus the cipher the gnome created was readable only with a special decoder, which had been disassembled and hidden; and even then, actually operating the decoder was a puzzle in itself. Sure, the gnome’s plan wasn’t perfect (the players were able to read his notes in the end), but the situation is plausible. The gnome was at least trying to make things difficult.

#3. Unintended Solutions

It helps to imagine that the puzzle’s architect had no solution in mind at all; that the only way to solve the puzzle is to “break” it. Of course, you as the GM create the solution, but it should appear to the players as if they’ve discovered some flaw in the obstacle’s design.

In another adventure I ran, the PCs came across a large tree that they had reason to believe housed a hidden gate to Alfheim, the world of the elves. The elves, secretive by nature, had hidden the gate with a simple illusion that made the tree look and feel solid, even though there was in fact an opening in the trunk. However, there happened to be a pond nearby, and if any PCs paid careful attention to it, they found that the reflection in the water revealed the opening in the tree. Once they had discovered this clue, it was only a matter of experimentation until they had found a way through the illusionary wall. The clue was subtle and natural enough that the players felt as if the elves simply hadn’t accounted for the pond giving their secret away.

Along the same lines, you should definitely allow the players to progress if they find an alternative solution to the puzzle that you didn’t think of. One of the most memorable role-playing moments I’ve had came from such a situation. A snake-like monster with a human head and nearly impervious scales had challenged the players to a duel, and all they had to do to win was spill one drop of the monster’s blood. I had intended for this to be a grueling battle in which the PCs would wear down one part of the monster’s natural armor until they finally had pierced her flesh. However, one player came up with the ingenious idea to climb above the monster, wait until she was taunting the heroes, and then leap onto her head, causing her to bite her tongue.

#4. Incidental Puzzles

Sometimes a puzzle has no architect but comes into existence naturally. Perhaps the heroes come across an essential artifact that has been shattered. In order to use it, they need to find all the pieces and figure out how to put them back together in the correct arrangement.

Another version of an incidental puzzle is a battle with a foe that has a particular weakness or that inhabits an environment that grants an advantage to the players if they can find it. You can see a good example of a “puzzle battle” in this video by Drunkens & Dragons.

#5. Tests of Intelligence

Probably the only time the GM gets to use a stereotypical puzzle in an adventure and preserve believability at the same is if the puzzle is specifically meant to test the brainpower of the player characters. For example, the PCs may be trying to join a wizards’ guild, but they must first prove their intelligence by completing a series of trials.

Alternatively, the PCs may find themselves in a dungeon created by a madman, like The Riddler from Batman, who suffers an inexplicable compulsion to leave clues for his enemies. Or the PCs might be participating in a contest of wits, like the old “Challenge of Champions” adventures from Dungeon magazine (if you’ve never heard of them, look them up).

*  *  *

To sum up this rant, it’s possible to insert puzzles into an adventure without breaking the players’ sense of immersion. You simply need to pause and consider what purpose the puzzle serves in the game world and why it has a solution at all. Believable puzzles are not only fun for the players to solve, they also strengthen the plot and setting of your game.

In upcoming posts, I’ll be talking more about how to design effective puzzles and including more examples of successful puzzles I’ve used in the past, so stay tuned!