Muscles bound in a unique alloy, armor that is tough enough to tank the toughest of blows, even from the likes of All Might in his Prime, hands that can morph into launchers that fire missiles made of explosive bone fragments that automatically seek out the heat signature of whatever living thing he lays his eyes on and subconsciously targets.

And to top it off, a size that rivals Gigantomachia when he hasn't grown, and a strength that far surpasses Gigantomachia even when he is grown.

In the MHAverse, Ultimate Humungousaur is best described as a sheer force of nature. His alloy muscles tighten and adapt in battle in accordance to the type of impacts he takes and damage he his hit with, meaning like Hulk in Marvel, he can grow stronger as he takes attacks. This isn't infallible as a powerful enough blow can knock him out before he adapts, but nevertheless a formidable component to his power.

Unfortunately, he no longer possesses the original Humungousaur's size changing ability. However, considering how powerful he is already, that's not exactly a handicap.

However, as with the other Ultimates currently while the Ultimatrix Function is still new, the form puts a tremendous strain on Ben's body and cannot be used for long. However, as Ben grows to used to the Ultimates more and begins to gain the ability to use them at will, villains best be very careful, and be sure to start running the moment they see Ultimate Humungousaur approaching.

https://www.deviantart.com/misakalovesyou/art/MHA-Rise-of-Ben-10-Ultimate-Humungousaur-866648877