*When the akuma meets a sans who is bloodier, crazier, scarier, and has more red dye than him:

【No au】aurora 【Aurora】Judgment Song

When epic sans and super sans meet dust sans: (but this may be a little different)

Tianyuan Sans Music-Avatar (Gods Descend to Earth)

ZD Ink Alter Ink Sheep

Horror egypt shake

Undertale: Past Present Future / The Three Major Tenses of Warts? - Mindless Soulless