2 or More
Players sit around the console and you enter any online game type, single player. For every kill you get the person to your right takes a drink. Once you have died twice you pass the controller to the person to your left.
If someone gets a triple kill the direction is changed and the person to your left has to take a drink and the controller gets passed to them. If your shield reaches red at any point and you fully recover or you headshot someone you get to nominate anyone to finish their drink.
If you and another player both kill each other you have to finish your drink with another player of your choice at the same time.
Keep track of your kills, once the game is over the person with the most gets to nominate someone to take a shot.