The: World S Finest Assassin Music

and "Reincarnated Beat" : Instrumental pieces used during critical transition scenes. "Time with Dia" : A softer, character-focused theme.

: A signature track reflecting the dual nature of Lugh Tuatha Dé.

: A version of "A Promise" is also sung by the character Dia (voiced by Reina Ueda). Background Score (OST) The World S Finest Assassin Music

and "For You" : Part of the core soundtrack ensemble.

The main themes define the anime's identity and were released during its initial run in late 2021. Artist : Performed by Yui Ninomiya . and "Reincarnated Beat" : Instrumental pieces used during

: Features various OST playlists and unofficial remixes/covers.

The original soundtrack was composed by and covers a wide range of moods across the series. Key Tracks : : A version of "A Promise" is also

"Dark Seeks Light" from The World's Finest Assassin (English Cover)