Kelp Thing is an enemy of Mermaid Man and Barnacle Boy who appears in the episodes "Mermaid Man & Barnacle Boy VI: The Motion Picture" and "The Card."
Kelp Thing appears as muscular and wears a light green and dark green suit, a gold necklace, and has eyestalks like those of a snail.
Kelp Thing's only known power is flying.
Kelp Thing's one true weakness is tow-away zones.
Role in series
"Mermaid Man & Barnacle Boy VI: The Motion Picture"
His real appearance is in the TV show. Kelp Thing is also portrayed in SpongeBob's remake of The Real Mermaid Man and Barnacle Boy Movie, as he wants to steal Krabby Patties from the patty vault. He was to appear in both Drippy Bros. Studios Mermaid Man and Barnacle Boy film, as well as SpongeBob and Patrick's film, as the main antagonist.
He appears on a few of the cards that SpongeBob discards.