Brobot

Brobot is Mr. L's gigantic robot in Super Paper Mario. He is created to be shaped like Luigi's head. After Mr. L loses to Mario and his team in combat, Mr. L summons his giant robotic brother and fights Mario's team in a battle oddly similar to scrolling space shooters such as Gradius. Once he loses, Mr. L vows to face Mario again. He has kept his promise, for he comes back in Chapter 6-1, after Sammer's Kingdom gets destroyed by The Void. His new improved Brobot L-Type has arms and legs this time and is more powerful, able to swallow Mario and fire rocket punches at him. However, Mario uses Boomer to destroy Brobot.

Trivia

 * Brobot's name is a portmanteau of "bro" (a shortened word for "brother") and "robot".
 * Mr. L calls Brobot his "Metal Bro."
 * Brobot is the boss with the most HP in the Game, even more than the final boss Super Dimentio. Suprisingly, he has more HP than his improved form. However, the laser gun Mario, Peach and Bowser use does damage very quickly, counteracting the high HP.
 * "Mr. L"'s card description notes that he is a great inventor.