The rules are quite simple.
 
You have 70 "endurance" points.
 
roll d20 to drink up and subtract the result from your endurace points.
 
The winner is either the person nearest 1 or failing that, the person who downs the most drinks without pissing themselves.
 
Oh yeah, if you roll past 1, you piss yourself.
You can quit out and hold your score at any time.
 
Now.
Bottoms up