Amulet of Quoz

Remove Amulet of Quoz from your deck before playing if you're not playing for ante.

[Tap], Sacrifice Amulet of Quoz: Target opponent may add the top card of his/her library to the ante. If he/she doesn't, you flip a coin. If you win the flip, that player loses the game. If you lose the flip, you lose the game. Activate this ability only during your upkeep.