key concepts: understanding rules, modding, writing rules
context: for any number; online or a room with work tables and supplies; 30-60 minutes
This is an introductory modding exercise. Designers will change the rules of Tic-Tac-Toe in order to create new variations. Then they playtest their designs.
This exercise dates from my very earliest talks and workshops on game design. It has been a staple of just about every class I have taught and is part of every new student’s first game design class at at the NYU Game Center. The strength of this exercise is its utility - anyone can mod Tic-Tac-Toe and immediately experience how changing the rules impacts the gameplay. Plus it introduces fundamental ideas around structure, iteration, and systems.
Setup
At a minimum, designers will need paper and writing utensils. However, making more materials available to them will help spark ideas. Try dice, blocks, pawns, marbles, egg or sand timers, and other prototyping aids. Ways to draw out and share their ideas (whiteboards, sketch pads, markers) are also helpful.
Rules of the game
Rules are one of the defining aspects of game systems. To help everyone wrap their heads around this basic idea, have the group list out the rules of Tic-Tac-Toe (you can draw out a game in progress to help them remember how it works). As people shout them out, write down the rules on a whiteboard or other surface. Most likely, you will end up with a set of rules that looks something like this:
- play takes place on a 3x3 grid
- 2 players play together
- players alternate turns placing an X or an O in an empty square • 3-in-a-row of the same symbol is a win for that player
- if neither player can make a move, the game ends in a draw
Note that strategy guidelines (“play in the center first” or “block if your opponent is about to win”) are subtly distinct from the actual game rules. You can play the game poorly from a strategic perspective but still play by the correct rules.
- For discussion: Every game of Tic-Tac-Toe that has ever been played - whether on a chalkboard in a classroom or drawing lines with sticks on a beach - has followed these rules. The rules are the grammar for speaking the language of Tic-Tac-Toe. It’s mind blowing to think about the billions of hours of behavior that the simple rules of Tic-Tac-Toe have generated!
What can change?
With the rules of the game visible to everyone, brainstorm a list of what elements of the game might be changed in order to deepen or expand or just mix up the gameplay. You will likely end up with a list that that includes things like:
- grid size or shape
- winning conditions
- types of symbols you can draw
- where and how you can place a symbol
- permanence of symbols (maybe you can move them or erase them)
- number of players
- available time
If no one has brought it up yet, I like to ask a question at this moment. Is Tic-Tac-Toe FAIR? Of course, this is an open-ended question without a single correct answer. Yes, it is fair in that the two players follow the same rules in the same way. But no, it’s not really fair because whoever goes first has a strong advantage. Or maybe every game ends in a draw, so it doesn’t really matter who goes first.
The idea of Tic-Tac-Toe’s fairness (nor not!) leads to some interesting ideas about how a game might embody or depict unfairness - or inequality, or oppression by the powerful. As they redesign Tic-Tac-Toe, it might be that the designers are trying to “equalize” the two sides, so that the first player doesn’t have an advantage. Or maybe they want to lean into the inequality, and perhaps emphasize the game’s asymmetry.
The “classic” version of Tic-Tac-Toe is a fairly abstract game, with just “naughts and crosses,” on a grid, as they are termed in the UK. One more vector for possible changes to the rules of Tic-Tac-Toe would be modifying not just the logical rules of the game, but also what and how it represents. What happens if the Xs and Os are replaced with cats and dogs? Or houses and oil derricks? You can add something like this to the list of possible changes:
- the X and O symbols and what the game represents
Depending on how you are making use of this exercise, you could ignore the idea of making this kind of “content” change to the game’s narrative surface. (After all, it’s plenty challenging just to rebalance the logical system of the game.) Or - you could make it the whole focus of the assignment. Leveraging the problematic “unfairness” of Tic-Tac-Toe in an exercise about social oppression can be a powerfully elegant entrance into a very complex set of issues. These exercises are surprisingly adjustable to a wide range of contexts and uses. How you use them is up to you.
Let the modding begin
And then - it’s time to redesign Tic-Tac-Toe! Have designers work in pairs (although a group of 3 is fine too and a great way to try out a game for more players). One important tip is to not change too much: have them just modify one rule or two at a time and see how it changes things. If you change too much at once, it’s hard to know which changes are affecting play of the game in what ways.
Perhaps the most important advice you can give is to stop talking and start playtesting. We have a tendency to discuss and debate design ideas in the abstract instead of actually trying them out and seeing how they work in practice. Encourage participants to quickly start playtesting to see how their rule changes impact the game. Then make adjustments to their rules - and playtest again. This cyclical process of playing, analyzing, and redesigning is the essence of iterative design.
I love the designs that come out of this exercise! Sometimes a group “discovers” a design by adding elements (gravity + larger grid + 4 to win = Connect 4). Or they are inspired by unusual materials like a Rubik’s Cube to make a particularly intricate design. Perhaps one of the most elegant mods I saw made only a single change: they reversed the winning conditions (you win if your opponent gets 3-in-a-row). Try playing it - it’s a mind-bending game!
Playing with each other
If you have time, groups can play each others’ Tic-Tac-Toe variants and can talk about what they played. (If you are short on time, you can just have a few of the groups share their new designs.)
However, I like to go one step further and use the Tic-Tac-Toe variants as a chance to practice rule writing and communication. As a final step in the exercise - before you have groups share with each other - have each pair of designers write out the rules to their new version of the game. Encourage them to be as complete and explicit as possible. They are free to include diagrams and illustrations.
Then: half of the groups watch silently while the other half tries to play their game by following the rules they wrote out. You have to be very strict and NOT let designers try to explain their games to each other. See if the rules can explain the games all by themselves. Of course many players will have moments of confusion and misunderstanding - but that’s part of the lesson! If players are completely stuck, designers can help explain, but the goal is to come to realize how difficult it is to communicate rules well. And also to practice the maddening discipline of non-intrusive playtesting. Swap the groups so that everyone gets to playtest a game and everyone sees their own game being played.
There is always a lot to discuss at the end of this exercise. It is a great way to come to understand the fundamentals of rules and play: how small changes in a system can produce very unexpected results. Looking at many variations of Tic-Tac-Toe side by side, it is always surprising to see how just many ways there are to modify a single game. In a very short period of time, this exercise manages to encapsulate the entire game design process: analyzing a system, prototyping and testing changes, communicating to players. Long live Tic-Tac-Toe!