Place it at the reveal in a gameplay edit, just as the hidden player appears, then follow it with a Bruh reaction for the caught teammate and a Game Show Buzzer when the plan falls apart.
About this sound
This is a short, roughly six-second spoken warning delivered in a gruff, drill-sergeant bark: 'Wake up, maggot, there's a red spy.' The voice is loud, abrupt and deliberately over-the-top, turning a simple alert into a comic jolt. It feels urgent and ridiculous at once, like being shouted awake in the middle of a game, and it lands best as a sudden interruption.