Above is an example play of my game Odd. It’s a pure abstract strategy game, in both structure and spirit. Before I discuss it, here are the rules:

It’s for two players, and it’s played on any tessellated surface with stones of two colors.

Definition: A Group is a set of adjacently connected, like-colored stones on the board, containing at least 5 stones. The picture below shows a board with two groups on it.

Rules (of which there are only two)

1. The board starts empty and the players take turns. On your turn you must place one stone of either color on any empty space.

2. The game ends when the board is full. Player 1 wins if there is an odd number of groups on the board at that time and Player 2 wins otherwise. Important: when counting groups, count groups of both colors.

Of the (too many) games I’ve designed, I love only a tiny handful. In that group, Odd is the one I discuss least, I think because it was the easiest to design. It came to me complete in ~30 seconds, in the savant-ish way games come to the great Christian Freeling. It’s also the simplest of my games rules-wise (but not strategy-wise).

In contrast, my other favorites among my abstract games, Catchup and Carnivores, took time to get right. All that mentation leads me to talk about them. In the meantime, Odd quietly sits there, being what I want it to be.

I thought I’d end the silence by posting the example game above. Because it’s strategic, smallish board sizes are good for beginners, so I’ve presented a game played on 61-cell hexagon.

The game was between two players who had each previously played only a few times. Beginners often play Odd from the inside-out, the above example included. Experienced players have no such tendency – expert(er) games are more strategically interesting but hard for an inexperienced player to understand, so I decided to go with a beginner game.

Note that depending on your preferences, you can set the threshold minimum number of stones for a group, and in the example game above it was set to 5. This number may need to be different at high level play, for the sake of balance and because the minimum number should be higher for larger boards.

So what’s going on here? Well, the first thing to know is that, because each group must have a certain threshold number of stones in it to qualify as a group, you have to plan far in advance to create groups or prevent their creation, and the shape and placement of each group affects your ability to create or prevent the creation of other groups. It’s hard to describe how it feels in practice, but to me it feels like playing a few simultaneous games of Hex somehow multiplexed onto the same board.

For a board like the one in the example game, the Even player generally aims for 4 groups, and the Odd player usually aims for 3 or 5. In the example game above, you can see that Odd won with three groups.

These goals will vary depending on the board shape/size/tiling and the minimum number of stones needed for a group. I don’t yet know what combination of those factors will lead to the best possible experience.

A reasonable guess is that it’ll work best with a setup where Even tries for 4 or 6 groups, and the Odd tries for 3 or 5. To achieve that, the board should be a little bit bigger than the one in the example, and maybe a little oblong, while keeping the 5 stone minimum.

On the other hand, I’ve played some delightfully epic matches of this on hexhex7 board with minimum group size of 7. That version is really only for experienced players who love this kind of game – everyone else will feel hopelessly lost.

On a braggy side note, years ago I sometimes played the aforementioned hexhex7 version of Odd against the consensus best Hex player in the world (at the time – I don’t know who’s at the top anymore), and though he demolished me without breaking a sweat in every other connection game we played, I won Odd more often than I lost against him.

Anyway, if you want to try the game, I strongly urge you to start on a small board like the one in the example.