Ultimate Wolverine (real name James "Logan" Howlett) is a fictional character, a mutant in the Ultimate Marvel continuity and member of the X-Men. Wolverine has animalistic senses and reflexes (he has been known to track a person by scent alone, like a wolf) and three, foot-long claws that extend between the knuckles of each hand. However, Wolverine's most benefitial mutation is his greatly enhanced healing, which allows him to survive and recover from nearly any wound imaginable. This, combined with his adamantium-laced skeleton and bestial ferocity make him into one of the greatest fighters in the Ultimate Universe.

It is interesting to note that, in transferring to the Ultimate Universe, many inversions have been made regarding Wolverine and Sabretooth. For example, in the Ultimate continuity, Sabretooth stated that Wolverine is his father, although it has been revealed that he may have been lying. This is an inversion of Chris Claremont's original intention for the Sabretooth character as Wolverine's father.
Another inversion is that, in the Ultimate continuity, Wolverine served for a time as Magneto's elite assassin. In the normal continuity, Sabretooth operated as a mercenary and, later, an assassin-for-hire. Furthermore, though neither had any connection to Magneto in the original continuity, only Sabretooth was ever a member of the Brotherhood of Evil Mutants; in the Ultimate continuity, Wolverine was a highly-celebrated member of Magneto's Brotherhood of Mutant Supremacy long before Sabretooth was.