The Idol Nullifier is a talisman that can be used at Tribal Council. If the castaway wishes to use it, he must do so while casting his or her vote. At the voting booth, the user must write the name of the intended target on the nullifier and place it in the voting urn, along with his or her vote. If an idol is played on the intended target, the host will verify its authenticity, but will also present the Idol Nullifier, informing the player that the idol has been rendered powerless. If the target does not play an idol, the advantage will be wasted and its user will remain anonymous if he or she chooses to be. Similar to the Hidden Immunity Idol, the Idol Nullifier can be played until five castaways remain.
An Idol Nullifier can only negate one Hidden Immunity Idol, so it can be countered if a second Hidden Immunity Idol is played for the target.
On Day 34, Dean Kowalski was selected by random draw to go to the Island of the Idols. For his mentors' challenge, Rob Mariano and Sandra Diaz-Twine offered him a choice of three advantages—an Extra Vote, an Idol Nullifier, or a Hidden Immunity Idol good for the next Tribal Council which could not be played on himself— if he won a game of chance. Dean chose to play for an Idol Nullifier, which he then received after winning the game of chance. At the Day 37 Tribal Council, Dean used the Idol Nullifier on Janet Carbin, successfully preventing her idol from having any power, sending her to the jury.
The idea of the Idol Nullifier originated in Australian Survivor (2017), where the nullifier was designed as a regular Hidden Immunity Idol, but with a different use.
Instead of playing the nullifier in the voting booth, the contestant could play it as a regular idol, thereby reducing the uncertainty involved in using it.