Hugh Jackman's final outing in the role of Wolverine, also known as Logan, inevitably includes fighting. In fact, "Logan" is one of only a few R-Rated superhero movies, and it uses that rating to get extremely violent when he tangles with the cybernetically enhanced bad guys in the movie, known as the Reavers.
The question is, who are the guys Logan is going to be wrecking with his adamantium claws? Anyone who's checked out the trailers will have noticed the band of mercenaries in hot pursuit of Logan, Professor Charles Xavier (Patrick Stewart), and Laura (Dafne Keen), also known as X-23. Many of those mercenaries are decked out with cybernetic limbs - they're the Reavers, but they're a bit different from their comic book counterparts.
In the comics, the Reavers are a group of criminals who enhance themselves with cybernetic limbs and other augmentations and have a personal beef with the X-Men, and Logan in particular, for their many defeats. They're led by Donald Pierce, a cybernetically enhanced villain who replaces himself with more and more machine parts after every defeat.
That's not quite the story of the Reavers in the movie, though. They're still a group of cybernetically enhanced bad dudes, but they're essentially special ops military contractors working for evil biotech corporation Transigen (they're responsible for the X-23 experiments), rather than a crime syndicate.
Pierce (Boyd Holbrook) is still the leader of the Reavers in "Logan," and he's still decked out with a cybernetic arm. The team's circumstances are different, though. Pierce and the Reavers have no personal vendetta against the X-Men or Logan. In fact, at one point in the movie, Pierce tells Logan he's a fan. They run afoul of Wolverine and Professor X when the pair get mixed up in the Reavers' mission to recapture X-23.
And while Pierce is a major villain in the movie, he's not really a supervillain. He and his guys are more like hired guns. Logan battles them repeatedly, and lots of the nameless Reavers will get used up as cannon fodder throughout the film.