Petris is a game of controlling bacteria. Each player is a scientist who has to control the propagation of the bacteria under their supervision. Those bacteria are hungry and they are always looking for food in adjacent Petri dishes. Watch out! If left alone in a Petri dish bacteria will eat a lot and reproduce... making it much more difficult to control them!

During the game, players must manage and limit the propagation and spread of their bacteria. At each contamination scoring phase, players receive points for each Petri dish where they have more bacteria than their opponent. At the end of the game, the player with the fewest contamination points is the winner! This is a game of area minority - contain that bacteria!