Robot Mantis

The Robot Mantis is a robotic mantis supervillain who first appears in the episode "The Bad Guy Club for Villains."

Description
It is a green praying mantis-shaped robot with red glowing eyes and a skull-shaped head.

"The Bad Guy Club for Villains"
It is in the intro for the lost episode of The Adventures of Mermaid Man and Barnacle Boy, where it is seen attacking Abigail. Mermaid Man and Barnacle Boy see the Robot Mantis causing trouble, causing Mermaid Man to punch the robot's head and destroy it, defeating the villain.

SpongeBob Comics Annual Super-Giant Swimtacular No. 1
It appears in the bonus gallery poster along with nearly every other Mermaid Man hero and villain. Its name is revealed in the corner of the poster.

SpongeBob Freestyle Funnies 2018
It appears on the front cover along with many other villains.

Super-Villain Team-Up!
It is one of the many villains recruited by and  to infiltrate the Krusty Krab.

"Swamp Mates"
It appears as an action figure.