Place it right at the reveal beat in a reaction edit, after a build-up and before the payoff. Follow it with the Oh My God Wow Sound Button for a bigger second reaction, or precede it with Sudden Suspense to stack tension before the drop.
About this sound
A short 2-second voice clip of a man trailing off as he says 'Mother of me...' in stunned disbelief. It lands as pure exasperated frustration, the kind of half-finished reaction that feels both shocked and fed up. The clip is taken from the animated short Epic Rage Time: The Incredible Derp.