We are playing RTL with the TOI part of the game. When we reach the 5th level of the keep, and the Avatar makes his appearance, I know that the OL must get rid of his OL cards for the balance of the game. Since the Heroes have the Feat Deck, are they also required to rid themselves of these cards before the final battle?
Road to Legend with Tomb of Ice Incorporated - Final Battle Question
Yes, all Feat cards are discarded when the avatar appears (see FAQ).