Mini SpongeBob looks similar to the real SpongeBob, except it is squarer, does not have any holes, and is a lot smaller than the real SpongeBob. He also does not have a belt on his pants. Mini SpongeBob's nose is not the same as SpongeBob's, because Mini SpongeBob's nose is a small little stub, and SpongeBob's is an oval shape and longer. In his "Best Day Ever" appearance, he is shown to be bigger, and more realistic. He had holes, dressed exactly the same way, and looked more like SpongeBob. It could be possible that SpongeBob redesigned it.
Role in series
He debuts in the episode "Squid Wood." He was created to replace Mini Squid, who was given a job by talent scout Milo J. Finkerfish. He reappears in the episode "Best Day Ever," where SpongeBob used him as a decoy to get past the guard, though he had puppet strings.