warrior

A person who is actively engaged in battle, conflict or warfare; a soldier or combatant.

• [Link:] Gee, it sure is boring around here. [King Harkinian:] My boy, this peace is what all true warriors strive for.

A person who is aggressively, courageously, or energetically involved in an activity, such as athletics.figuratively

Anything exceptionally tough, stubborn, or that is hard to conquer or overcome.figuratively

• It was an old warrior of a hole about sixty feet deep, that had broken the hearts of numerous gangs of well-sinkers, all of whom abandoned it[.]