He has an appearance similar to Frankenstein's monster. He has a muscular body and he has a human nose. He has greenish grey skin. He has a black mullet hairstyle with sideburns. He has two tower like conductor coils on his back.
He wears black pants with lines on them with a triangle dash in the middle that glow green. He has stitch like lines on his arms (right arm: half of his shoulder and left arm: half way from his glove). He has brown gloves with his fingers showing. He has 3 black bolts on his chest and 1 black bolt on each side of his neck, all bolts have a green line on them. He has white lines on his waist that connects it to the Omnitrix. He wore the Omnitrix symbol on his waist.
In Ultimate Alien, His skin is completely grey. His gloves are now grey and so are his tower like wire coils. His belt is now grey and a grey hexagon is where his Omnitrix symbol used to be. The bolts are now grey and now have no green line on them. The Ultimatrix symbol is now on his chest.
In Omniverse, the 16 year old version has a shorter haircut , lacks bangs and has a mullet, but still has evident sideburns. His skin has several uneven seams, combining grey-brown skin with darker grey skin. He also has large pink scars across his chest and right arm. He retains the bolts on his neck, but no longer has them on his chest; instead he has one on each shoulder and elbow. The bolts are now bronze, and resemble a flathead screw with a green light in the crease. His belt is now green with white stripes, which have white bolts in them, and another bolt as a buckle. His turrets are now green with screws on them; the coils are now white and feature green bulbs at the tips. His gauntlets are now green with bolts on their knuckles, his legs are now a greenish-black color, and his "boots" are now copper with three green slits on them. His teeth are now yellowed and uneven. The Omnitrix symbol is embedded in the flesh of his right pectoral, with several deep scars sprouting from where it resides.
Enchanced Everything: He has enchanced intelligence, strength, and durability.
Electrokinesis: He has two conductor coils on his back that allow him to generate and manipulate lightning and electromagnetism. He can emit powerful lightning bolts and magnetize his feet to attach to metal structures