The game progresses by counting up from 1 to 21, with the player who calls "21" suffering a drinking penalty before the next round starts.
This was created in the Swan and 3 Cygnets pub in Durham City by Alan Smith, Ian Crosby, Stephen Rickaby, Andrew Barras, Paul Nicholson, Kieran Walker, Gavin Southwell, Mark Thompson, Brian Griffin, and Paul Jones.
[citation needed] Players are arranged in a circle, facing inwards.
For example: As the game progresses, each player in turn must recite one to four numbers, counting in sequence from where the previous player left off: If a player makes a mistake, then they suffer a small to moderate drinking penalty (e.g. 2 fingers of drink) and then restart the game from 1.
Andy, Bill, Cath, Dan, Ed and Fran are sitting with Andy at 12 o'clock, and the other players arranged clockwise in alphabetical order: The game ultimately finishes when all the numbers have been replaced, by rule changes instigated by the person who drinks on 21.