Neither of them really did any big plays. The plays they claimed were underwhelming (Caroline with how she misplayed her idol and Feras with the pretend find of the idol).he technically saved himself. A bigger move would have been not to play the idol at all
In the end though I think Feras played a very good social and somewhat strategic game. He had an a strong ability of reading people, position himself so he's not a target of a vote, forming alliances and how he used the idol (note not "played" the idol) as a way to not make him a target.
I think he was aware that the opposing alliances were not going to target him because they were never in a position to split the vote on him.