Grey Matter
General Information
Species Galvan
Home World Galvan Prime
Body Humanoid
Alternate Counterparts Albedo (Albedo's Ultimatrix's Galvan)
Grey Matter (Ben 10,000 Timeline)
Grey Matter (Race Against Time Timeline)
Powers and Abilities
Abilities Enhanced Intelligence
Enhanced Agility
Enhanced Flexibility
Enhanced Jumping
Wall Crawling
Sharp Teeth
Underwater Respiration
Long Tongue
Voice Actor Richard Horvitz (Original Series)
Kari Wahlgren (Gwen)
Carlos Alazraqui (Race Against Time))
Eric Bauza (Omniverse)
First Appearance Washington B.C.

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


Grey Matter is a grey-skinned, frog-like, bipedal alien that is only four inches tall with large green eyes, which have rectangular pupils. He wears a white jumpsuit with a black stripe going down it.

In the original series, Grey Matter wore the Omnitrix symbol on his back and his eyes were yellowish-green. He spoke with a high-pitched voice.

In the original series, Gwen as Grey Matter has Gwen's hair and more oval shaped eyes, with much smaller pupils. She wears a light blue jump suit with dark blue sleeves. She wears the Omnitrix symbol on her back. She also lacks the stripes Ben's form has.

In Ultimate Alien, Grey Matter wore the Ultimatrix symbol on his chest.

In Omniverse, 11 year old Grey Matter looks exactly the same as the original, but his collar is now black. His skin tone is also different.

16 year old Grey Matter now has a green jumpsuit with a black belt. His suit collar is now black, and the stripe on his head and jump suit are no longer present. He wears black, fingerless gloves with a green rectangle. His neck is slightly longer. His Omnitrix symbol continues to be present on his back, and his voice is slightly deeper.

Ben 11 as 

Powers and AbilitiesEdit

File:Grey Matter's intelligence.png
Grey Matter's small size belies his great calculative and technical intellect. He can create complicated machines from spare parts and understand the function of any device at a glance. Grey Matter's intellect serves as a problem solver and analytical help in difficult situations.

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 tiny suction cups 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 in Ultimate Weapon, and in So Long, and Thanks for All the Smoothies, he was able to break a coolant pipe to freeze the Vreedle Brothers.

According to Derrick J. Wyatt, Grey Matter is amphibious and has gills.[1]

Grey Matter has a long prehensile tongue, owing to his insectivore nature.


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.


Original seriesEdit

  • Grey Matter first appeared in Washington B.C..
    • Grey Matter was searching in cereal boxes for a Gold Sumo Slammer card.
  • In Hunted:
    • Grey Matter defeated Kraab and Sixsix.
  • In A Small Problem:
    • The Omnitrix malfunctioned, trapping Ben as Grey Matter for most of the episode.
  • In Secrets:
    • Grey Matter defeated one of Vilgax's drones.
  • In Truth:
  • In Grudge Match:
    • Grey Matter defeated one of Slix Vigma's drones.
  • In Ultimate Weapon:
    • Grey Matter snuck into a building, let Gwen and Max come in and opened a safe.
  • In They Lurk Below:
    • Grey Matter saved a drowning man.
  • In Ghostfreaked Out:
  • In Back With a Vengeance:
    • Grey Matter appeared when Ben unlocked the Master Control
    • Grey Matter appeared in a photo.
    • Grey Matter tried to escape from Vilgax and Kevin.
    • Grey Matter escaped Kevin on a Null Guardian.
    • Grey Matter tried to escape a Null Guardian.
    • Grey Matter was accidentally transformed into to get back at Gwen.
  • In Midnight Madness:
    • Grey Matter was hypnotized into being Gwen's slave.
  • In Merry Christmas:
    • Grey Matter accidentally destroyed the Rustbucket's air conditioner and later destroyed the Jingleator.
  • In The Unnaturals:
    • Grey Matter stopped some thieves from stealing the Liberty Bell and won an MP3 player in a contest.
  • In Be Afraid of the Dark:
    • Grey Matter escaped Zs'Skayr and built a sungun.
  • In Perfect Day:
    • In a dream, Grey Matter defeated a mutated Cash and JT.
  • In Secret of The Omnitrix:
    • Grey Matter defeated Dr. Animo.
  • In Ben 10: Destroy All Aliens:
  • In Snack Break:
    • Grey Matter failed to retrieve his snack in a vending machine.

Ultimate AlienEdit



  • In Double or Nothing:
    • Negative Grey Matter explains that he won't attack Ben, Gwen, or Kevin anymore. Shortly, it is revealed Albedo can only be Negative Grey Matter for about a second before reverting back.





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Naming and TranslationsEdit

Language Name Origin
Bulgarian Сиво вещество From сиво, grey and вещество, matter.
Croatian Siva Tvar From siva, grey and tvar, matter.
Deutsch Graue Eminenz From Grau, grey and Eminenz, eminence.
Dutch Grijze Massa From grijze, grey and massa, matter.
Finnish Harmaa Haitta
French Le Tétard Gris From gris, grey and tétard, tadpole.
Hebrew תא אפור From תא, cell and אפור, grey.
Hungarian Ragacska From the ragacs, putty.
Italian Materia Grigia From materia, matter and grigia, grey. Materia grigia also means brain in Italian.
Norwegian Gråbarken From grå, grey and barken, bark.
Polish Szara materia From szara, grey and materia, matter.
Potuguese (Brazil) Massa Cinzenta From massa, mass and cinzenta, grey.
Romanian Cerebel From cerebellum.
Romanian Materie cenusie From materie, matter and cenusie, grey.
Russian Гуманоид From Гуманойд/Gumanoyd, humanoid.
Serbian Сива Материја/Siva Materija From сива/siva, grey and материја/materija, matter.

Spanish (Spain)

Materia Gris From materia, matter and gris, grey.
Spanish (Latin America) Materia Gris From materia, matter and gris, grey.
Sweden Grå Dvärgen From grå, grey and dvärgen, dwarf.
Turkish Gri Madde From gri, grey and madde, matter.
Greek Γκρίζα Ύλη From Γκρί, gray and ύλη, matter
Arabic جراي ماتر
Korean 미니그레이 From 미니, mini- and 그레이, grey.


Ben 10Edit

  • 4' Grey Matter
  • Metamorfigure Grey Matter (Binoculars)

Ben 10: Alien ForceEdit

  • Alien Creation Figures from (Ben 10) Diamondhead and Grey Matter

Ben 10: Ultimate AlienEdit

  • Alter Aliens Ben to Grey Matter and Goop to Way Big


  • According to Derrick J. Wyatt, Grey Matter is Ben's smartest alien.[2]
  • As shown in Ken 10, Grey Matter is smart enough to unlock the Prototype Omnitrix's Master Control.
  • It was revealed that neither Azmuth nor Albedo was the source of Grey Matter's DNA sample.
  • A running gag in the original series is that when Ben selects an alien with enhanced strength, he gets Grey Matter instead.


See AlsoEdit

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