Topple
Oracle Text
Exile target creature with the greatest power among creatures on the battlefield. (If two or more creatures are tied for greatest power, target any one of them.)
Card Rulings
10/4/2004 It can only target a creature with the greatest power. This means you pick such a creature on announcement, and if that creature is not still the one with greatest power on resolution, then this spell doesn’t resolve since its target is illegal.
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