Starcraft term; when attacking a base, the "Hero Marine" is a Terran Marine that survives an engagement that destroys most of the other units/Marines and goes on to destroy the Nexus/Hatchery/Command Center to shut down the expansion.

Also used sarcastically to describe an idiotic and overly-motivated Marine who thinks that yelling "oorah!" is the same as getting actual work done. See also motard, motivator, blue falcon.
The platoon had to police-call one square kilometer because a Hero Marine lost his night vision goggles.
by 9-Line June 14, 2017
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