The roulette game is simple. You place a single bullet in a six-shot revolver, spin the clip and point it at yourself. If you're lucky, you'll hear the click of the hammer on an empty clip. If you're unlucky... well, you get kicked from the channel.
If you're an Opper, you have the fun feature to point the gun at someone else
!roulette [nick]
The optional [nick] parameter only works if you have opper status (an at-hat). Otherwise you point it at yourself anyway.