|Powers and abilities|
|Abilities|| Super Strength|
|Voice Actor||Dee Bradley Baker|
|First Appearance||Prisoner Number 775 is Missing|
Ultimate Wildmutt is the evolved form of Wildmutt.
Ultimate Wildmutt is significantly larger and more muscular than Wildmutt. His fur is maroon-red color. He has four huge gray/white spikes running down its back that overlap. These spikes start out as a shark-like fin at the head and rising almost into an arc over the back, tapering near the rump. He also has a long tail whose tip has a horn resembling a scorpion sting. His lips are black, like Wildmutt in the original series. Ultimate Wildmutt wears the Ultimatrix symbol on his chest.
Powers and Abilities
Ultimate Wildmutt has Wildmutt's incredible sense of smell and is physically stronger than him.
- Ultimate Wildmutt first appears in Prisoner Number 775 is Missing, where he defeats Prisoner 775.
- In The Ultimate Enemy: Part 2, Ultimate Wildmutt was used to help Gwen and Kevin defeat the Flame Keepers' Circle Soldiers.
Ben 10: Ultimate Alien
- Ultimate Wildmutt's appearance is similar to a Fel Hound from World of Warcraft.
- Ultimate Wildmutt is one of Ben's aliens who is not in the Ultimate Alien intro; the others are Fasttrack, ChamAlien, Eatle, Jury Rigg, Shocksquatch, Clockwork and Ultimate Way Big, although this is due to their existence not being known until Season 2.
- Ultimate Wildmutt is one of four aliens to have debuted as a toy before their television debut. The other three were Upchuck, Eatle and Clockwork.
- Ultimate Wildmutt is the last Ultimate form used in Ultimate Alien.
- Ultimate Wildmutt did not appear in The Ultimate Sacrifice.
- His toy form doesn't have lips on the upper side of his mouth like in the show.