Amulet of Quoz

Remove Amulet of Quoz from your deck before playing if you're not playing for ante.
{T}, Sacrifice Amulet of Quoz: Target opponent may ante the top card of their library. If they don'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 only during your upkeep.