If a mandatory trigger is missed by its accountable player and missing that trigger is advantageous for them, this penalty is a [Warning] instead.
§ 702.2.e Tournament Rules PDF (officieel)
§ 702 Game Play Errors
§ 702.2 Missed Trigger [No Penalty]: The accountable player for a triggered ability doesn’t demonstrate awareness of the trigger before the first time it would have an observable impact on the game.
