|Homeworld|| Galvan Prime
Galvan Mark II
|Powers|| Small size|
|Voice|| Richard Horvitz (Original Series)|
Kari Wahlgren (Gwen)
Carlos Alazraqui (Race Against Time)
Yuri Lowenthal (Albedo)
Eric Bauza (Omniverse)
|First Appearance||Washington B.C.|
Grey Matter has gray skin and is very frog-like. He is 6 inches tall. He has greenish-yellow eyes with a black dash going through them, and wears a jumpsuit similar to Ben's. He wears the Omnitrix symbol on his back.
Ben 10: Ultimate Alien
He is the same as in Ben 10, except that the Ultimatrix is black and green and on his chest.
Ben 10: Omniverse
He looks the same as in Ben 10. On young Ben, the only difference is that his neck is now black. On teen Ben, he wears a different, green-and-black jumpsuit and his head stripe is gone.
Powers And Abilities
He posseses great intellect and can calculate anything in seconds. His intellect can help him in very diffucult situations. His size also allows him to squeeze through holes and small openings. Grey Matter appears to be stronger then he looks as he was able to break a pipe out in So Long and Thanks for all the Smoothies. According to Derrick Grey Matter is ampfibious and has gills.
Grey Matter first appears in the episode Washington B.C. where he is in the M-Mart looking for the gold sumo slammer card in all the cereal boxes. Gwen then comes and picks him up to yell at him until he transforms back into Ben.He makes his second appearance in Hunted where he sneaks onto Kraab 's head and pulls out some of his wires causing him to go haywire and crash, defeating him. He then jumps onto Sixsix and messes with his jetpack causing him to fly into the water tower defeating both Sixsix and Kraab. He is then talking with Tetrax about how smart he is until he changes back.
He appears in A Small Problem where he accidentally transforms at a water park. As he tries to get revenge on a man who didnt let him on the ride, Howell Wayneright sees Grey Matter and tries to catch him. Grey Matter then runs to Gwen and races her down the slide. When they get to the bottom, after Gwen leaves Howell Wayneright comes up from behing Grey Matter and catches him. Grey Matter tries to call Gwen for help but he is then put in a container as Howell runs off. When they get to Waynerights house, Grey Matter tries to escape the bottle he is in but has no luck, then Howell takes a picture of Grey Matter. After Howell leaves Grey Matter gets the cat to push the bottle off the table freeing himself. Then mini vacumes chase Grey Matter down a hallway until he climbs up to safety andfinds a phone. He then uses the phone to call Gwen and tell her only part of where he is, because when he touches the window a security system activates knocking him and the phone back which causes the phone to break. He then runs through a vent to hide from Howell, but when the fans turn on Grey Matter gets pushed out. He then runs while Howell chases him with a broom until he jumps in a sink and ends up in a toilet. He then turns off the security cameras and tries to escape through the chimney, but howell lights a match threatening to smoke him out. Grey Matter then falls down into Howells net and is put in a cage. When the Forever Knights show up, they Grab Grey Matter and Howell, and bring them to their castle. Grey Matter then meets Enoch, and watches as they take him to a laboratory. When Grey Matter gets their he sees a wooden Grey Matter strapped to a table and being cut by lazers. He is then strapped onto the same table, but Howell comes to his rescue by taking out the forever knghts. After more knights arrive, Grey Matter runs out of the room and runs into Gwen and Max. Gwen picks up Grey Matter and they try to run out the castle, but instead get trapped in another room. Inside the room with alien tech, Forever Knights attack and Grey Matter uses his brain to combine a phew things to make a bomb, however before he can escape he turns back into Ben.
In Secrets Grey Matter was used to help save Gwen as he defeated one of Vilgax's Drones on The Chimerian Hammer.He returns in Truth, where he is used to attack the Null Guardian causing it to land on Phills car. Next Phill is about to shoot Grey Matter with the Null Void Projector, but thanks to Gwen he uses a mirror and reflects the projector right back at Phill.
In Gwen 10, Gwen uses Grey Matter thanks to Ben, and she has to run around the forest away from a raccoon that is chasing her.
He appears in Grudge Match where he is attached to Kevin Levin. He is used to help the contestents escape and take out some of the robot guards. Later they are trapped by even more guards but Grey Matter is able to control one of them and defeats the others.In The Ultimate Weapon, Grey Matter was used to sneak inside a building, but their were two dogs inside. Once he got away from the dogs he was able to open the door for Grandpa Max and Gwen. Later he unlocked the safe but when Enoch showed up, Grey Matter had to attack him. He was thrown onto a table and almost fell in the paper shredder. Once Grey Matter escaped the shredder he was able to go up a pipe and get out of the building into a dumpster.
He appeared in They Lurk Below to help save a man who was in the water. He went in to attack the two sharks and all he had to do was punch one of their eyes causing them to leave.
In Ghostfreaked Out, Grey Matter appears to get away from Ghostfreak and attack the Circus Freak Trio. Once he escaped he timed out.He makes eight appearances in Back With a Vengeance. First, he is used when he finds out he unlocked master control and is testing it out. He is used again when taking a picture with Grandpa Max and Gwen. Next he is used to get away from Vilgax but he is quickly captured again. Later Grey Matter makes three seperate appearances when trying to get away from the Null Guardians. He appears in the end in order to hide from Vilgax and Kevin in the Null Void. Lastly, he appears on accident when trying to use an alien on Gwen.
In Midnight Madness Grey Matter was hypnotized by Sublimino. Gwen took advantage of this and made Grey Matter do her bidding until he timed out.
He appears in Merry Christmas twice. First he is used to attempt to fix the air conditioning in the RV, except it doesnt work and the RV ends up breaking down next to christmas town. He appears later when he is looking for the power source and once he finds it he shuts it down.gmm
In The Unnaturals Grey Matter accidentally appears to try and stop a few robbers. With help from Grandpa Max, he is able to jump into the criminals car and take it apare causing them to crash down. He then lands in a bucket of jellybeans. He then uses his brain power to figure out how many jellybeans there are and win a music player.
He appeared in Be Afraid of the Dark , where he is used to escape and hide from Zs'skayr and Dr. Vicktor, and he was working on something to help him right before he timed out.
In Perfect Day , Grey Matter was used in a dream to save Grandpa Max from a mutaded J.T and Cash.He appears in Ken 10 twice, both used by Kenny. First he is used to sneak out of his room to join Bens fight which doesnt succeed. Next Grey Matter is used to unlock the master control on his Omnitrix.
In Ben 10: Secret of the Omnitrix , Grey Matter appears on accident and ends up defeating Dr. Animo and stops the DNA bomb.
Ben 10: Race Against Time
In Ben 10: Race Against Time, Grey Matter makes a small appearance where he is used in a shop. He is used to get revenge on Cash and J.T by using a machine to spray soda on them and has food fly everywhere making them run away out of the store.
Ben 10: Destroy All AliensIn Ben 10: Destroy All Aliens, Grey Matter makes one appearance. He is used accidentally while being held by the Retaliator. He hides from him by climbing down his arm and running away to his house. He is safe until his mom freaks out and starts trying to attack him with a broom. He avoids the attacks until he transforms into Diamondhead.
Ben 10: OmniverseGrey Matter returns in Omniverse in the episode Have I Got a Deal for You. He makes a cameo appearance on accident because the Omnitrix isnt giving him the alien he chooses. After Grey Matter is used he quickly changes alien forms into Nanomech. In So Long, and Thanks for All the Smoothies he makes an accidental transformation. He is used to climb on theceilign and pull outone of the pipes causing a cold substance to spray out onto the Vreedle Brothers making them frozen. He is then seen interrogating the Vreedle Brothers until they see someone flying off with Rook's ship. Grey Matter then uses his brains to find the tractor beam and bring the ship back before turning back into Ben.
He appears in Of Predators and Prey: Part 2 as an accident when fighting against Humungousaur's predator. He then jumps on top of the predator and uses a technique Khyber used, by pinching a certain spot on its back to make the predator fall to the ground.
He returns in Rad where he is used to come up with a brilliant plan to escape the incuseans. While thinking he finds out he can understand Pyxi and has a conversation with it. Grey Matter then finally comes up with a plan as he gives everyone orders. While the rest of the team went to do there jobs, Grey Matter and Pyxi worked on fixing the Lovely Duck. Once Grey Matter repaired the ship, they took off as he transformed back.
Ben 10: Omniverse
Y: Means that this alien was used by Ben in that episode.
N: Means that this alien was not used by anyone in that episode.
S: Means that this alien was used by someone other than Ben in that episode. (hover over the letter to see by who)
- "Anything but being a micro munchkin."
- "Sure wish I knew what I was talking about."
- "Aww man, for once I was better off as me" - They Lurk Below\
- "I'm thinking....." - Rad
Grey Matter's name comes from the fact that he is grey.