According to the Spongebob Squarepants fan-wiki (because of course that exists), Primitive Sponge only appears in one episode of the Nickelodeon cartoon, wherein he and prehistoric Patrick get ...

Along the way they'll visit alternate forms of Bikini Bottom as it is warped by SpongeBob's mind into prehistoric ... Each of its six playable characters – SpongeBob, Patrick, Squidward ...