Rules FAQ
- You are only eligible to choose a revealed character that isn’t a copy of a unique character in either player’s dead pile nor a copy of a unique character that’s already in play
Reaction: After you win a challenge as the attacking player, reveal the top 5 cards of the losing opponent's deck. You may put a character revealed this way into play under your control. Place the other revealed cards on the bottom of that player's deck in a random order. (Max 1 per challenge.)
Link: Decklists
Rules FAQ