Ultimate Humungousaur is the evolved form of Humungousaur.
Ultimate Humungousaur is an enormous ankylosaurus-like creature, being 20 feet tall and easily dwarfing the normal Humungousaur in size. His skin is green and he possesses a dark blue, spiked shell. His tail also has a mace on the end of it. His knuckles have barrels on them, which he can transform into four-barrelled missile launchers at will.
Ultimate Humungousaur has tough, green skin and nearly impenetrable armor plating similar to an exoskeleton. His muscle fiber has increased greatly, making him exponentially stronger than before. He is powerful enough to easily overpower one Humungousaur and hold his own against an army of them. In Ultimate Sacrifice, it is shown that he can lift Way Big, which shows that he is one of the strongest aliens in Ben's Ultimatrix.
As a result of millions of simulated battles over a millennium, Ultimate Humungousaur's genetic DNA allows him to form his hands into bio-Gatling guns that shoot kinetically unstable bone fragments as missiles.
- .According to the Cartoonnetwork Ben 10: Ultimate Alien mini-site, Ultimate Humungousaur has the ability to grow to 120 ft tall. However, it was confirmed by Dwayne that the site is wrong, because since Ultimate Humungosaur can not grow at all.
- Ultimate Humungousaur was Albedo's first evolved form and was the last alien he used with the Ultimatrix.
- Despite being a third of the size of full-size Humungousaur, Ultimate Humungousaur is stronger than full-size Humungosaur.