Rule 801.11

If a spell or ability requires information from the game, it gets only information from within its controller's range of influence. It doesn't see objects or events outside its controller's range of influence. Example: In a six-player game where each player has range of influence 1, Alex controls Coat of Arms, which reads, "Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it." Coat of Arms will boost Alex's creatures based only on what creatures are controlled by Alex, the player to Alex's left, and the player to Alex's right. It won't take other creatures into account. Example: In the same game, Rob is sitting to the right of Alex. Coat of Arms will boost Rob's creatures based only on what creatures are controlled by Rob and Alex. They are the only two players within range of both Rob and the controller of Coat of Arms.

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