Hero Duels is a twist that appeared in Survivor: Ayia Thekla. The twist forced one person from each of the losing tribes at every Immunity Challenge to face off in a duel, hoping to win the second Immunity of the round.
Throughout the pre-merge portion of the season, only one tribe was awarded Immunity at the conclusion of every challenge. The remaining two tribes would then have to select one person to compete in a condensed version of the same challenge. The individuals chosen to participate were selected by the "team captains" of each tribe - Andrew T., Blake B., and Nick M.. The winner of the duel won Immunity for their entire tribe that round, while the loser's tribe would be sent to Tribal Council.