The clip comes from the Warhammer 40,000: Dawn of War games, where Imperial Guard squads announce enemy units they spot during real-time battles. Short unit responses like this became easy to lift, share and reuse because they are instantly recognisable to strategy players and carry the grim, militaristic tone of the setting. On soundboards and in fan edits, the Eldar warning is now used less as a literal game cue and more as a shorthand joke for spotting a rival, an outsider or an unexpected threat.