Transformice is a hectic online multiplayer game which is part co-op, part everyone go ballistic. On each level there is a piece of cheese and a mouse hole, and the idea is to run and grab the cheese, then take it back to the hole.
Mix this with numerous fun glitches, and shaman trolls and you get pure and utter chaos. With 66 maps, as many as 80 psychotic mice bent on getting the cheese first, and Shamans who have no idea what they are doing the game quickly turns into a hilarious and unpredictable mice frenzy.
Every round, player with the highest score (or in some stages, the two highest scores) is chosen to become a Shaman. However, if a player has already been Shaman for an amount of turns, another player is chosen. The Shaman can spawn several different kinds of objects to aid their fellow mice to acquire the cheese. The Shaman is the most powerful player, and has the ability to affect whether the mice are able to obtain the cheese or not.
Mice represent Transformice users. Every round, mice interact and compete with one other to return a piece of the cheese to a mousehole with the fastest time possible. Physical objects created by the shaman mouse or spawning with the level are affected by the movement of mice, and vice versa. Certain levels allow mice to collide with each other as well.