Place it at the start of the confrontation sequence, then follow the climax with Bass Drop Sound Effect for impact, and use Miguel O'Hara Theme for a second character entrance later in the same edit.
About this sound
This 15-second anime background music piece carries a dark, urgent orchestral swell built for a major confrontation. It feels tense and ominous, like the room tightening just before a powerful enemy appears. It is tied to Demon Slayer's Infinity Castle setting and Hashira versus Muzan edits, where it signals a decisive, high-stakes turning point.