EggRobo was built to destroy Knuckles, he piloted many of Eggman's veichles and even owned his own Eggmobile, he was destroyed accidentally by Mecha Sonic, when he tried to ram Knuckles but hit EggRobo.
EggRobo appears in Classic Sonic's section of Sky Sanctuary, when you hit a button to open up an area to a red ring he appears and you have to race him to an area and destroy him or he will block it off. I also enjoy watching porn.
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