This line comes from Pokemon Stadium, the Nintendo 64 battle game where players watched Pokemon fight in 3D arenas with commentary-style announcements. The wild one from the word go phrase fits the moment a wild Pokemon shows up ready to fight, and that ready-for-anything tone is why soundboard users saved it as a standalone clip. Online, creators reuse it far beyond Pokemon, dropping it into reaction videos and gaming montages whenever something unpredictable appears, because the short, confident delivery instantly sets up a surprise without needing any context from the original game.