A totally unfair fight
Four against one is a totally unfair fight, especially if those on the four side are armed with guns, while the loner is armed only with a pocketknife. Oh! Did I mention that the lone fighter is an ex-Marine? With those facts, the fight's outcome is a foregone conclusion: Ex-Marine — one bruise and a small cut; Assailants — one dead, one seriously wounded, two in custody. Gotta love the Marines.