Place it right after the betrayal is revealed, following It Was At This Moment He Knew, so the threat works as the payoff. Then cut to Fail Sound Meme when the revenge plan falls apart, keeping the sequence focused on one character's grudge.
About this sound
This 17-second clip is a single spoken line, delivered in a heated, threatening tone as the speaker insists he wants to kill someone. The blunt wording and rising anger make it feel intense and unsettling, yet its over-the-top delivery gives it a dark, comic edge for reaction use. It lands as a dramatic outburst rather than a casual remark.