|Powers and Abilities|
|Equipment|| Laser Guns|
Energy Buzz Saw
|Relatives|| Sevenseven (older brother)|
Eighteight (older sister)
Twotwo (younger sister)
|Alias|| Metalmouth (Kraab)|
|Voice Actor||Dee Bradley Baker|
In his armor, his feet are hooved. He has purple pads covering his central joints, an alien like belt, and four central lines to provide outlines for his face, which are his eyes and mouth. When his black and pink mask is broken, it reveals an ugly, mutant, gray-yellow creature with pink and gray robotic eyes and four arms. He is somewhat similar to a predator from the Alien vs. Predator franchise, as most predators wear masks to hide their faces.
In Omniverse, his appearance hasn't changed much. His jumpsuit is now a much more reddish color, the black highlights are now a dark blue, and the silver armor plating has a blue tint to them too. Most of his pouches are smaller and the ones on his shoulders are no longer sunken in.
Sixsix first appeared in the episode Hunted, where he along with his rivals Tetrax Shard and Kraab were to take the Omnitrix from Ben and give it to Vilgax for the reward, but he and Kraab defeated by Grey Matter.
In Ben 10: Secret of the Omnitrix, Sixsix was a prisoner on Incarcecon, then became Vilgax's helper. His mask was broken completely, revealing that Sixsix is an ugly, mutant-like, light gray creature with robotic eyes. Sixsix was defeated by a great source of feedback from the Omnitrix.
In Cough It Up, he along with his siblings was hired by Psyphon to get him a precious item. They found Argit (who had the weapon) and fought for it with Ben, Rook and Spanner. He defeated Spanner but was knocked out by Buzzshock when he was about to take Argit. After Sevenseven defeated the rest of them, Sixsix was saved by him. At the end of the episode he got banned from Undertown.