my game spike sisters was two-player by accident. it was designed as a game where one player has to manage two characters with different limitations (one’s short but wide and one’s tall but narrow: they squeeze through a maze of spikes). but because the two sisters are controlled simultaneously – one with the keyboard, one with the mouse – having a different human player move each of the sisters is as natural as having one player control them both. and that doesn’t mitigate the challenge of having to coordinate two different characters: coordinating two human players has its own considerable challenges.

when talking about board game, people use the word “scales” to describe how well a game handles a varying number of players. this game plays great with five players, but it also works well with seven or three: it scales well. i like when digital games scale well. a lot of games can be jury-rigged into two-player games just by having one player hold each side of the controller, but not all games are well-suited to that kind of division of labor. toru iwatani’s libble rabble works great two-player because the game involves coordinating two avatars who move independently (two characters with a line stretched between them, which they use to cordon off areas of the game screen).

the slut and i have been seeking out games to play on our ipad. hurdle hell is, like it sounds, a game about jumping hurdles, but it features two characters on two separate tracks, each of whom jumps when one two big square buttons is pressed. as a one-player game, it’s about coordinating two button-presses that are slightly out-of-phase with one another: the left hurdler’s hurdle may come sooner than the right hurdler’s, or the left hurdler may have to wait for a slow-moving fireball while the right hurdler jumps a fast-moving bonfire. the difference in timing between the two obstacles becomes greater and greater as the game escalates.

then we started playing it together, slut controlling the left hurdler and i controlling the right. and the game isn’t, i think, cheapened this way, because it becomes a slightly different kind of challenge. reacting to and timing a jump over your own obstacle, not being faked out by your opponent’s. i’ve made it as far through the game’s stages working with her as playing alone (with her watching). when most games are designed to be played by a single player or (more rarely) group of players first and have the “opposite” mode just tacked on, it’s neat to see a game that scales just as naturally to a two-player experience as a one-player experience.