https://youtu.be/25COCysupac
We only take the Seiyaryu turbo as an engine, because playing Holy Night as a whole sucks. The engine is 2 Seiyaryu (easily searchable, play 2 as backup), 3 Rayel (add Bellfire/Nativity), 3 Bellfire (add Seiyaryu/Rayel), 3 Nativity (add/ss Seiyaryu from hand). So, basically this Seiyaryu turbo needs
Nativity+1 LIGHT fairy. Some Holy Night card we could play for recovery is Flamel (recur Seiyaryu from GY, niche battle disruption) and Advent (recur from GY/ss Seiyaryu from hand).
Since Nativity needs LIGHT fairy fodder, it makes sense to play the LIGHT fairy good stuff. Diviner is 1 card VFD by sending Trias Hierarchia, use Trias tribute Diviner, use Diviner ss Valkyrie Sechste, use Sechste ss Sigrun, make VFD. Artifact is good too since they're impactful fairies and also Nativity shuffles back the fairies, it means we don't have to run multiple copies of garnet. Eva is there as we can summon it through Diviner and it gives us Herald of The Orange Light with its effect online. We are able to run Extravagance as we dont need many extra deck monster to play.
The recursion line depends on several cards only, like Trias (it wont banish itself if used in VFD), Holy Night Flamel/Advent, and Eva. We don't run another lv7 LIGHT dragon as they're all bad cards and we need fairy fodder for Nativity, not dragon.
Pros: Unique playstyle with strong lock like VFD/Scythe.
Cons: The recursion and end board are weak.