Eye Guy is the Omnitrix's DNA sample of an Opticoid from the planet Sightra.[note 1]

Eye Guy's entire upper-body is covered with green eyes, around 20 of them; although he ironically has no eyes on his face, which consists of a mouth and a very large pair of elastic[2] bat-like ears. He has dark tan skin on his back and feet, with a lighter tone of tan on his chest, armpits, face, and hands. His entire skeleton is made of cartilage, not bones.[OV Brief 1]

In the Original Series, Eye Guy wore black pants with white bands on them and a white belt with the original Omnitrix symbol on it. He had light green eyes with dark green pupils, and one giant primary eye in the center of his chest.

In the Ultimate Alien intro, Eye Guy looked the same as before, except his feet were darker and the big eye on his chest was replaced by his Ultimatrix symbol.

In Omniverse, 16-year-old Eye Guy's eyes are now bigger, recolored slightly brighter, and placed symmetrically on his body. His chest eye is now closed by default, and he now has two additional eyes on his palms. His pants now have green cuffs replacing the white bands; the main belt where the Omnitrix symbol is located is recolored green with a white stripe; and he additionally wears green cuffs on his hands. Much like in the case of Cannonbolt, Eye Guy's teeth may alternate between being sharp like his Original Series design or being flat.

11-year-old Eye Guy looks mostly the same as he did in the Original Series, albeit he has the palm eyes, eye placement, and pupil color of his 16-year-old self. He wears black foot sleeves; white bands respective to the green cuffs; and the original Omnitrix symbol on his belt is recolored green.