We've been ignoring "next turn" abilities for cards played on the last turn. I've adopted this interpretation for two reasons:
1. If it's the last turn, there is no next turn to trigger the ability.
2. Under normal play your opponents have a chance to select and play a card that could counteract any "next turn" abilities before they're resolved. You wouldn't have that for a card played on the last turn.
Any thoughts? Can we get an official ruling from Donald?
"Next turn" abilities played on the last turn don't do anything, since there is no next turn.