Squidward Tentacles is an alternate universe version of Squidward Tentacles, who is from a universe where Squidward is a clown.
He looks like the normal Squidward, except that he wears makeup similar to a clown's, and wears a purple and white colored clown costume.
He appears at the end slapping his head after SpongeBob
realizes that Super SpongeBob SquarePants
is the superhero of Bikini Bottom 2