Maha, Its Feathers Night + Crovax, Ascendant Hero

Prerequisites

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Steps

1. 1All nonwhite creatures your opponents control will have base toughness 0, and die as a state-based action due to having 0 toughness unless there is another effect increasing its toughness.
2. 2Whenever a nonwhite creature enters the battlefield under an opponent's control, it will have base toughness 0, and die as a state-based action due to having 0 toughness unless there is another effect increasing its toughness.

Effects

• Lock
• Nonwhite creatures opponents control die upon entering
• Reduce the toughness of most creatures opponents control