Defend your train against the oncoming horde of AI controlled robots which run, fly, rocket and roll in pursuit. Enemies are fully destructible and physically simulated (not animated) making for infinite variation in the carnage which you unleash. Neural network control allows for a wide variety of enemies which attempt to maintain the chase even when their parts have been damaged and destroyed. A variety of weapons and power-ups to unlock. Game Center enabled with achievements to unlock and scores to share.