The accountable player for triggers sourced from battlefields depends on control of the battlefield and is not automatically the player who brought the battlefield to the game. See CR 190.6. For more information on battlefield abilities.
§ 506.1.a Tournament Rules PDF (officieel)
§ 506 Triggered Abilities
§ 506.1 Accountable Player: The player responsible for putting a triggered ability on the chain, as defined by the core rules. See CR 383. Triggered Abilities for more information on triggered abilities.
