Eggrobo

EggRobo (also written as (エッグロボ) Eggrobo or Egg Robot) is an red, yellow and gray, red-eyed egg-shaped humanoid robot resembling Dr. Robotnik. It first appeared as an enemy in the game Sonic & Knuckles. In Sonic's storyline in that game, it only appeared as standard badnik enemy in the Sky Sanctuary Zone, after being seen launched from the Death Egg.

They are rather more prominent in Knuckles' storyline, however, as the EggRobo replaces Dr. Robotnik as the end-of-zone boss in every level up until the Hidden Palace Zone (in all of Knuckles' appearances prior to this, he had been allied with Robotnik). The EggRobo does not appear as the boss of the Flying Battery Zone, since the sprites used to model Dr. Robotnik for that boss were different and no equivalent sprites for the EggRobo were produced. The EggRobo also appears in cutscenes in the game. At the beginning of the game, while Knuckles is relaxing along with some of his animal friends, the EggRobo drops a bomb in their midst that scares his friends away. The EggRobo is destroyed by Mecha Sonic MKII in the Sky Sanctuary Zone (the final level in Knuckles' storyline). The EggRobo restrains Knuckles, allowing Mecha Sonic MKII to charge at him, but Knuckles breaks free and Mecha Sonic MKII destroys the EggRobo instead.

EggRobo later appears in Sonic R as an unlockable character. It has abilities similar to Dr. Robotnik's in that game, being capable of launching missiles, though EggRobo is slow for an unlockable character. It is unlocked by getting all the five Sonic Tokens in the Regal Ruin course.

EggRobo also appears in Sonic Adventure 2 as a kart racing VMU Download with his own stage, and again in Sonic Adventure 2: Battle as Rouge the Bat's unlockable sub kart, obtained by getting all the emblems of Rouge's missions.

An Egg robo appears in Sonic Chronicles as a cameo next to a Sega Genesis and an Egg Capulse in the Metropolis Zone. There is also a boss named 'Egg Bot' fought in Metropolis Ground Zero, however, this robot looked more like a robotic version of Dr. Robotnik.