The man with the metal hand who runs security for the company that made Laura, and who is sent to bring her back.
Donald Pierce is the cybernetically enhanced leader of the Reavers and the head of security for Alkali-Transigen, the company that bred the children in Logan. Boyd Holbrook plays him. He is the one who tracks X-23, which makes him the face of the pursuit for most of the film.
Minor spoiler
He is killed by the other children from the program, the ones Laura was trying to reach, who turn their powers on him together.