Airania, Trapped World

Airania, Trapped World enters the battlefield
with 5 charge counters.
At the beginning of your upkeep, remove a
charge counter from Airania, Trapped World,
then if it has 0 charge counters, you lose the
game and if it has 25 charge counters, you win
the game.
Sacrifice a creature: Put a charge counter on
Airania, Trapped World.