one person starts with the piece of paper. they draw an object or person. then they pass it to the next person, who draws an object or person that 'beats' the object or person preceding it. the game continues in this manner until the players lose interest or a clear winner is determined. often played covertly in class.
dude, sweet drawing war game yesterday: started with rihanna, moved on to chris brown, then a rabid pitbull, then michael vick.