Place it at the end of a confident claim, then follow it with Bruh for a quick follow-up, or open with Emotional Damage before it for a bigger reaction chain.
About this sound
This clip is the spoken phrase 'What the sigma?' pushed through an extreme bass boost, so the words hit low, distorted and deliberately over the top. It feels absurd and confrontational, like catching someone in a ridiculous moment and answering with pure disbelief, and it works best as a sudden, exaggerated reaction.