All characters in the game are pigs that have been turned into zombies. The zombie pigs want to kill humans. Each pig starts with a suite of Traits, one is called the Ability and it as an attack, either melee or ranged. This is the only attack the pig can make, and ranged attacks are apparently made with "a projectile weapon bolted on". The remaining Traits are called Abilities and they allow the pig to perform certain actions. Pigs gain experience points by killing humans and accumulated experience points can be spent to gain additional Traits. The rules apply primarily to combat.