Tom Hermans 
How to make a good puzzle — Explorables Jam 2018 entry
August 19, 2018
The Rubik’s Cube. Sudoku’s. Video games. Puzzles are everywhere, but just how do you make a good puzzle—one that’s fun, and satisfying to solve?
I’ll explain this with levels from Sokoban, a puzzle game where you push boxes to the correct spaces on the grid. I’m demonstrating my points using this game, but they can be applied to most types of puzzles. Since puzzle design is subjective, your mileage may vary, but this is a good starting point that I’m also using for my own puzzle games.
I’ve split my tips into three categories: Presentation, how puzzles are displayed to the solver, Elegancy, how a puzzle should be set up to make it comfy to solve, and Aspiration, how a puzzle (or puzzle game, specifically) can become something special.
Presentation
A good puzzle should explain itself
Here’s one example of a Sokoban puzzle with bland graphics, and an identical one with proper metaphors for objects. Both use the same underlying rules, but which one is easier to learn how to play? If the player has an expectation of how an object will react before attempting to interact with it, that will help them learn and understand the puzzle faster. This is the single most important function of art in a puzzle game, so don’t underestimate it.
(In case you’re wondering—just click on an example, then use [Space] to begin, [Arrow keys] to walk, [Z] to undo, and [R] to restart. You can also open them in a new tab, which supports has mobile controls.)
A good puzzle shows all puzzle pieces
These two examples have the exact same level and rules, but the first example is from a first person perspective while the second one is top-down and allows you to see the whole puzzle. In the second example, it’s much easier to learn and understand the puzzle. Make sure the way you choose to represent your puzzles is also the one that’s the most comfortable for analyzing and solving them.
Presentation take-away 🥡
A puzzle should be inviting and rewarding. The designer should always subtly push the player towards the correct solution. You might want to obscure parts, but that makes it harder to learn how the puzzle works, so don’t. Basically, a good puzzle wants to be solved!
Elegancy
Use the smallest amount of space and puzzle pieces for the puzzle will work
Ideally, you want the player to spend the most time thinking about a puzzle, and as little time as possible to input that solution into the puzzle to see if it works as intended. This is why puzzles should be in their smallest solvable setup, to make it easier to interpret and understand the puzzle. Hence, when you start with the left puzzle, you’ll have a lot of friction, whereas the right puzzle is smaller, and less miscommunication can occur.
A red herring is a puzzle element that seems relevant, but isn’t required to use to solve the puzzle. It’s clutter, and thus unnecessary. A better idea would be to place objects that seem useless initially, but are actually used in completely new and unexpected ways, making them relevant.
Understand possibility space
The bigger a puzzle becomes, the larger it’s possibility space gets. This possibility space is the number of different states the puzzle can be in. So the starting scenario would be one state, and moving left would move the puzzle into another state. Moving back right would restore the original state. But pushing the block below you downwards opens yet another state with the block moved. If the above game, you can see the states that your action would result in for the four direction you can walk into every turn.
If you keep at it long enough, you’ll arrive in a solved state, or hit a dead end. The minimum amount of steps between start and solution is a good measurement of how difficult a puzzle is. It’s tricky to calculate exactly how big the possibility space is, but generally: the bigger the level, and the more things you can do on that level, the bigger the possibility space. Generally, a large possibility space makes a puzzle harder, but also prevents players from brute forcing the solution, so it’s very much a double-edged sword.
If you want to play more with this concept, try out PuzzleGraph.
Elegancy take-away 🥡
Usually, minimalist is the way to go to respect the player’s time as much as possible. We have tools to analyze how ‘hard’ a puzzle is, but actually playtesting it is also really important to see how players perceive difficulty.
Aspiration
A good puzzle wants to teach the player
Once you know how to solve a Sudoku, you’ve solved them all. You can keep solving them, but you won’t learn anything new. Is solving the same puzzle multiple times with a different coat of paint really that interesting?
These example both have two puzzles. The first puzzle in both is identical, it’s about getting through walls of crates. In the left game, the second puzzle is another version of puzzle one, but longer. The second example has a new second puzzle showing another side of the ‘pushing through walls of blocks’ dilemma. If the designer wants to keep teaching you new things in every levels, puzzles become much more focused and elegant.
A puzzle will generally consist of different components that interact with each other. In most games, these are introduced separately, ramped up in difficulty, and then thrown in the mix with other puzzle mechanics the player has already learned, opening up new interactions between them. No puzzle lives in isolation from the others, and this is why you need to be careful with the ordering of puzzles.
A good puzzle (game) should be ambitious
Generally speaking, the more original and clever the game’s core mechanic, the more interesting the game and it’s puzzles. That’s why we’re seeing crazy puzzle games about warping space or time travel or… rolling sausages over grills. Sokoban is not very original, so it probably is not the best to demonstrate my point here… but I’m gonna try anyway. Both of these examples have the same puzzles, but present them very differently—the second game has a bit more continuity, and even a bit of foreshadowing…
This is why most good puzzle games take place in mysterious worlds—to add a layer of mystery to the already mysterious puzzles. That’ll help to give the player motivation to keep solving the puzzles—they want to see where it’s all going, after all. This is also why puzzle games allow themselves to be a little player-unfriendly from time to time.
Aspiration take-away 🥡
Puzzles should be a little bit inaccessible if they want to evoke a feeling of mystery and sensation to drive the player, and to make them eager to learn, explore and experiment with its systems.
Final words
I hope this made you realize designing puzzles is, in fact, very much a puzzle in of itself.
Are you itching to make puzzles now? You can load Puzzlescript, and make new levels using the example projects, or make a new puzzle game with rules written from scratch.
Playtesting is also a very important part of making a good puzzle game, more so than with other types of games. My article about playtesting could be a very nice follow-up for you. And to plug myself even further, you can try my puzzle games Tahira’s Tower and Sokobanana to see how I apply these rules to my own work.
Sources
This article was mostly inspired by “A Good Puzzle Game Is Hard To Build”, an interview with puzzle designers about what makes a puzzle game good.
Other sources include Game Makers Toolkit’s video “What makes a good puzzle?” and this interview series by devmag: “How are puzzle games designed?”
Some of the puzzles here were adapted from Microban and Autosokoban. All interactive widgets here were made using Puzzlescript.
This article is a submission to the Explorables Jam. This is my first explorable, so if you’ve read to the end and have a bit of free time, consider giving me some feedback! Contact info is on the top right of the page.
Tom Hermans: Professional game designer and hobbyist game dev
