Wolf O'Donnell is a male wolf and the leader of Star Wolf. He appears in the Star Fox games as the rival of Fox McCloud. As such, he often appears shipped with Fox, either in a competitive, forced or consensual relationship.

In the game, Wolf acts as the opposite of Fox. While they both run military teams, Wolf works for the opposing side, and is typically shown as the darker, more evil one between the groups. His work is also considered more criminal than Star Fox's. Despite this, in certain games, Wolf has shown to have a mutual respect for Fox and sometimes assists his rival when the situation calls for it.