Unstoppable comes from Unreal Tournament, Epic Games' fast-paced arena first-person shooter series, where a dramatic announcer calls out a player's growing killing spree. The voice lines became a signature part of the game's over-the-top presentation, and clips of them circulated widely in gameplay videos, montages and memes long after the original matches ended. Because the word is instantly understood even without context, editors still use it to signal dominance, momentum and a run that opponents cannot seem to stop.