Rule 801.7a

If a trigger event includes an object moving out of or into a player’s range of influence, use the game state before or after the event as appropriate to determine whether the triggered ability will trigger. See rules 603.6 and 603.10. Example: Carissa and Alex are outside each other’s range of influence. Carissa controls a Runeclaw Bear owned by Alex and they each control an Extractor Demon, a creature which reads, in part, “Whenever another creature leaves the battlefield, you may have target player mill two cards.” The Runeclaw Bear is destroyed and is put into Alex’s graveyard. The ability of Alex’s Extractor Demon doesn’t trigger because the leaves-the-battlefield event was outside Alex’s range of influence. The ability of Carissa’s Extractor Demon does trigger, even though the creature is going to a graveyard outside her range, because the leaves-the-battlefield event was within her range.

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