If you make it on Redemption Island and it's your turn to go back into the game you get a choice.
Either
1. You can just enter into the game like normal
OR
2. You can challenge a remaining castaway to a duel. If you win the duel you take there spot and they take your spot on Redemption Island. But if you lose the duel then you're eliminated.
So if there is someone who back stabbed you and you want to mess there game up, beat them in a duel and now they are stuck on Redemption Island.
