Russian Roulette

Russian Roulette enters the battlefield with 6
bullet counters on it. Additional time counters
cannot be placed on Russian Roulette.
At the beginning of each upkeep, choose a player
and a number between 1 and X, where X is the
number of bullet counters remaining, and roll a
die with X sides. If the die lands on the chosen
number, the chosen opponent loses the game.
At the beginning of your endstep, remove a
bullet counter from Russian Roulette.