According to Entertainment Weekly, the Idol Nullifier gives "its owner the right to nullify a hidden immunity idol, as long as the owner played it on the right person at the right time."
The new power has been widely criticized by many fans of the show, who feel like SWAT cop Dan Rengering got a raw deal when the Idol Nullifier was used and he was eliminated because if it.
Now, Probst is speaking out about the controversial moment, saying, "The Nullifier blocks the use of one specific idol played for one specific person."
"If Dan had a second idol, he could have played it, and barring another Nullifier with his name on it, he would have been safe. So that attempt to save Angelina by playing his first idol, thus maintaining the numbers advantage for the Goliaths, proves very expensive," he went on to say.
Dan reportedly felt afterwards "that he would have had to play both idols at once to escape nullification," which Probst also addressed.
"He certainly could do this, but there would be no need since he could wait and play it after a Nullifier was played," the host said. "This is the great thing about the Nullifier: Its mere existence adds another layer of uncertainty to the game."
"It was the first time a Nullifier was played and Carl played it correctly. That's all we could have ever dared dream when we put the Nullifier into this season. The other side of the moment was the confusion shared by Dan and the Goliaths," he continued. "They had no idea there was even such a thing as a Nullifier so their shock was compounded by a lack of information. And that lack of information connects to the third and perhaps most important element in all of this — the reminder that the Survivor gods are the ones who are truly in control of the game."
"The Survivor gods have a wicked sense of humor and they love a healthy dose of irony. So, this was a match made in Survivor heaven. Dan's confidence was growing by the day. He had just played an idol for Angelina and still had one in his pocket," Probst also said. "There was 0.0 chance of him going home if he played it. He was already looking ahead, making his next move and planning how to get out of camp to go find another idol."
"Dan was going to win this game. Because the idol is unstoppable… until it's not. That's one of the great lessons the Survivor gods teach us. Things are what they are… until they're not. The idol can no longer be assumed to be unstoppable," he added. "The idol has a new foe and the mere knowledge that the Nullifier exists adds another layer of doubt. Oh, those tricky Survivor gods know what they're doing."
Survivor airs Wednesdays at 8 p.m. ET on CBS.