GGJ 2012 Diversifiers :
Asymmetry: (Every player is different) The game requires more than one player, but each player has entirely different goals and rules.
Collaborative Casual/Hardcore: (Two players: one casual, one hardcore) Collaborative play for two, but one player has more to do than the other (or the difficulty level is different between them).
Followers: (Increasing number of NPCs follow you) The game involves a growing number of autonomous non-player characters that are always following the player character’s position.
Hive mind: (3+ players control the same avatar) Player avatar is controlled simultaneously by 3 or more people. They don’t have to, but may, control the same aspect of the character.