Idol Rivals is a twist that featured in Survivor: East Timor and Survivor: El Salvador. It is a twist to Hidden Idols, where each castaway is given two 'rivals' who must be voted out before the merge. The twist was brought in to coincide with the "Revenge is Sweet" theme of East Timor, where two pairs of former rivals from past seasons returned to the game. The twist was reprised twenty seasons later for El Salvador, with a reduced rival count to one person each. It is the opposite of the Idol Bonds twist which appeared six seasons later in Moral vs. Merciless.
Each player is allocated either one or two players who are dubbed their "idol rivals". In East Timor, one rival was on their own tribe, while the other was on the opposing tribe. In El Salvador, there was only one rival for each player, who was someone on their original tribe If all ones idol rivals are voted out before the merge, the castaway receives a standard Hidden Immunity Idol. The castaways have to make ties with the opposite tribe in order for them to vote out their idol rival. Due to this twist, no other idols are up for grabs, so it is the only way the castaways are able to get a leg-up on their opposition.