When the Fangpyre battled the Ninja in Ed & Edna's Scrap N Junk, they attempted to turn the fight in their favor by biting a statue that Ed was making in Jay's honor. The Fangpyre venom transformed the sculpture into a fully functional robot, which immediately began attacking the Ninja with its large nunchucks. Jay defeated the robot by commandeering a Fangpyre Wrecking Ball and using it to knock the robot off its feet.
When the Ninja arrived at the Ed & Edna's Scrap N' Junk pursued by Fangpyre, Ed and Enda decided to rebuild the Mechanical Ninja to protect the junkyard.
The robot was very large in size and primarily green in color, with the exception of its red, snake-like eyes and pink-purple nunchucks. After being rebuilt, it was blue and grey, with yellow-tinted hands and purple nunchucks.
- The Fangpyre Robot is one of three Serpentine machines in the cartoon series without a corresponding set. The other two vehicles are the Serpentine Bus and the Serpentine Train (although it did have a planned set, the idea never reached full production).
- The Fangpyre Robot may be the cartoon equivalent of the Fangpyre Mech set, which never actually appeared in the show.