Dungeon Games

At the beginning of each player's upkeep, that
player flips a coin. If they win the flip, they put
a +1/+1 counter on target creature they control,
a quest counter on Dungeon Games, and create
a colorless Treasure artifact token with "{t},
Sacrifice this artifact: Add one mana of any
color." If they lose, they sacrifice a creature they
control.
When there are four or more quest counters on
Dungeon Games, sacrifice it.