As far as I know it's a mix from the My Little Pony series which has an episode where Princess Luna becomes Nightmare Moon and the song Sonne by Rammstein.
Oh so first i went to gacha club and I took screenshots of the characters moving on a green screen next I put the clips into all light motion and I added the background and the shadow. I edited the characters on ibisPaint X after that i added a lighting overlay (you can find one on Pinterest) and thats it!💕