He has the same appearance as Plankton, but wears a yellow crown, a red Santa-like coat, and a shrinking belt around his waist.
Role in episode
Plankton decides practicing in ruling the world by shrinking himself into SpongeBob's aquarium full of sea chimps. The king of the chimps immediately gives his crown to Plankton and goes away. Plankton's royal life is going fantastic until a sea chimp knocks him out. Plankton then wakes up tied, while other chimps (along with the former king) prepare to sacrifice him for a huge tongue, which turns out to be Patrick's while he's drinking the water with sea chimps. Plankton tells the chimps to tie the shrinking belt around them all so they can go out, but Plankton fails to do so while other chimps grow big.