Rule 801.10

Spells and abilities can’t affect objects or players outside their controller’s range of influence. The parts of the effect that attempt to affect an out-of-range object or player will do nothing. The rest of the effect will work normally. Example: In a six-player game in which each player has range of influence 1, Alex casts Pyroclasm, which reads, “Pyroclasm deals 2 damage to each creature.” Pyroclasm deals 2 damage to each creature controlled by Alex, the player to Alex’s left, and the player to Alex’s right. No other creatures are dealt damage.

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