Place it at the exact reveal point, after a short build-up and before the reaction shot lands. Follow it with the WTF Boom Sound Effect to double the impact, then cut to a calm clip so the entrance stands out in the edit.
About this sound
This 1.3-second clip is the Kool-Aid Man's loud, booming shout of 'Oh Yeah!', delivered in a deep, exaggerated voice that fills the whole moment. It feels gleefully overconfident and absurd, like a sudden burst of cartoon energy crashing into a quiet scene. It comes from the classic commercials, where the pitcher character smashes through a wall to deliver the line.