Greymatter (Prime Timeline)

Grey Matter is the Nexomnitrix's DNA sample of a Galvan from the planet Galvan Prime.

Ben as Greymatter
Grey Matter is a grey-skinned, frog-like, bipedal alien that is only four inches tall with large green eyes, which have rectangular pupils and horizontal eyelids. He wears a white jumpsuit with a thin vertical black stripe going down it (a larger version of the same stripe exists on his head, in-between his eyes).

Greymatter wears a green Galvan tunic with black sleeves and a black stripe running down his chest and abdomen. A black belt surrounded his waist. The platings were colored silver and covered more of his neck, shoulders and wrists, as well as his legs and feet, leaving his toes exposed. His eyes were light green.

Gwen as Greymatter
Gwen as Grey Matter had Gwen's hair and more oval-shaped eyes, with much smaller pupils. She wore a light blue jumpsuit with dark blue sleeves. She wore the Omnitrix symbol on her back. She also lacked the stripes Ben's form has.

Powers and Abilities
Grey Matter's small size belies his great calculative and technical intellect. He can create complicated machines from spare parts, understand the function of any device at a glance, and make sophisticated repairs to complex machines, (such as a warp-drive engine). Grey Matter's intellect serves as a problem solver and analytical help in difficult situations. This allows Grey Matter to think more strategically when brute force is inefficient.

Grey Matter's brain capacity makes Ben smarter about things he's never even seen before, like Kraab's alien circuitry.

Grey Matter can sometimes manipulate living things by stimulating certain parts of their nervous system if such beings can be controlled by external stimuli.

Grey Matter's size allows him to squeeze into small spaces and can climb walls due to microscopic pads on his skin. He also has sharp teeth and his slimy skin makes him difficult to grab.

Grey Matter appears to be stronger than he looks, as he was strong enough to move a cleaner's bucket with mops in it and break a coolant pipe to freeze the Vreedle Brothers.

Grey Matter is amphibious and has gills.

Grey Matter has a long prehensile tongue, owing to his insectivore nature. As a Galvan, he also possesses a 'pre-brain' which deals with all basic bodily functions.

Grey Matter was able to understand Pyxi's speech.

Weaknesses
Grey Matter's small size makes him unsuitable for physical battle, so he must outsmart his enemies in a fight. Animals like dogs and cats can be a problem, as they may see Grey Matter as a chew toy or food to them.

Despite possessing immense intelligence, Grey Matter can still make miscalculations, as his attempt to upgrade the Rust Bucket's air conditioner caused it to overheat instead, incapacitating the vehicle.