Duke is an extraterrestrial life-form made of raw Void Essence built up over time from space decay and living beings. he begins to show that he is anything but Knuckles. His eyes glow a bright neon green, he has a large third eye on his chest, green spiked knuckles on his gloves and broken metal restraints, and the collar of his shoes are green. his dreadlocks also glow the same color. Duke can take on any appearance, but likes Knuckles' form for the looks.