The line comes from Sonic Unleashed, the 2008 Sonic the Hedgehog game, where Sonic delivers the cheerful Woo, feelin good after a successful moment in play. Fans later clipped the short voice line and shared it on soundboards and in gaming edits, where its bright, confident tone made it an easy shorthand for feeling great. It spread because the delivery is instantly recognisable to Sonic fans and works without any context. Years later it still appears in reaction videos, montages and memes whenever a creator wants a quick, upbeat burst of confidence.