It is a green praying mantis-shaped robot with red glowing eyes and a skull-shaped head.
Role in series
"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 Marge. 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.
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.
It appears on the front cover along with many other villains.
It appears as an action figure.