Place it at the start of a Mauga push, just after an enemy callout and just before the team moves in. Pair Enemy Spotted first to set up the target, then this clip, then Okay Let's Go as the signal to attack.
About this sound
This is a short Mauga voiceline lasting about 1.3 seconds, in which the hero delivers the line about eyes like a demon in a deep, threatening voice. It feels menacing and confident, like a warning issued just before a fight, because Mauga sounds completely sure of himself. The line comes from Overwatch.