Egg Bro is a fictional troublemaker in various Go!Animate grounded videos, based on the Hammer Bro's from Super Mario Bros. Aside from being a typical troublemaker like most Go!Animate troublemakers and a Super Mario OC, not much is known about him other than the fact that he likes to throw eggs at people.
Egg Bro appears in All Star Smashers as a Primary Spirit, as a novice class, where you must fight both Tabatha the Tortoise and Sonny Slaven at McDonald's to obtain him. When fighting Tabatha and Sonny, Sonny will favour using his neutral B move. Also, both characters' Final Smashes will be different from their usual ones. Tabatha's will involve her cussing orders at McDonald's, while Sonny's will involve him saying "Loli" which almost always kills the player.