I control Fairgrounds Warden, Last Laugh, and three Treasure tokens. Fairgrounds Warden had exiled an opponent's creature, and I want to sacrifice the Treasures to trigger Last Laugh three times (and for the mana). If all creatures would die after the third Last Laugh trigger, did the opponent's exiled creature return in time to prevent Last Laugh's second ability from triggering, or do I sacrifice it?
While it appears as though the game moves directly from having Fairgrounds Warden in play to having the creature it had exiled back in play, this isn't exactly the case.
When Fairground Warden dies, the game has to process the end of its exile effect with a one-shot effect. This happens immediately and doesn't use the stack, but there's still a moment where neither creature is on the battlefield and in that moment, Last Laugh's sacrifice trigger will trigger and go on the stack when players next get priority.