@Marie The Skullgirl Yep. I got the idea from the Memories of Phantasm episode where Remilia fought Flandre in the sky above the mansion.

so is her shield we are fighting on...over the mansion?

You know your stuff when it comes to Touhou music. ;)

I should probably list the tracks in the description now that you mention it XD

(Part 2 of 2)

One last thing. I feel I've got quite a keen ear when it comes to Touhou covers. So for fun I've matched up all the BGM with their respective remixes.

music_loop.ogg = Scarlet Destiny by Sensitive Heart
https://www.youtube.com/watch?v=0TeJSHrVBss

music_loop2.ogg = Scarlet Chain by xi-on
https://www.youtube.com/watch?v=wRbKTqW2TPA

music_loop3.ogg = ツェペシュの幼き末裔 (Omnia album) by sound sepher (Jun.A)
https://en.touhouwiki.net/wiki/Omnia

music_loop4.ogg = 月時計 ～ ルナ・ダイヤル by UI-70
https://www.youtube.com/watch?v=RqdTyxV4h_M

NOTICE: If anyone reading this wants higher quality rips (gilvasunner not silvagunner lol) aka lossless FLACs of the music besides Youtube's limited .mp3 quality, you'll have to download it alongside a ~1.65 TB collection of all other Touhou music. Yes Terabites LMAO.
http://www.tlmc.eu/2018/01/tlmc-v19.html

(Part 1 of 2)

I find it interesting how, instead of using a sprite sheet for the background, you had 2 transparent scarlet mist layers overlap and move at different speeds in alternate directions to create a feeling of depth. It's an efficient touch that helps the stage feel more organic without needing hundreds of frames to do so.

The parallax effect at the edges is pretty cool as well. Where the giant blood moon moves with the camera but the mansion itself stays stationary. It really shows just how much of a massive impact the Red Mist incident had on Gensokyo.

I also like how the main spell card circle platform that you fight on is that same one that Remilia stands on when she respawns. It's good continuity like that goes to show how well it meshes with the Challenger Pack as a whole.