Abyssal Futo (Labyrinth of Touhou 2 Plus Disk)
While B4F Futo may have been one tough customer, Abyssal Futo is slightly easier, partly due to her different stats.
The biggest difference comes in the form of Abyssal Futo's ailment resistances. B4F Futo had strong resistance to PAR and HVY, had fairly high resistance to SHK and debuffs, and and some resistance to SIL. B4F Futo's only vulnerable ailments were PSN (which was extremely useful thanks to Futo's absurd speed) and TRR.
Abyssal Futo is still very resistant to HVY and has high resistance to SHK, but she is now neutral to PAR, SIL and debuffs. She retains the weakness to TRR but is actually highly resistant to PSN now. While you can't rely on PSN anymore, you actually have the option of stunlocking this version of Futo.
In terms of affinities, Abyssal Futo is still deathly weak to PHYS and highly resistant to FIR, but she is now neutral to SPI (Possessed Futo slightly resisted SPI) and CLD (Possessed Futo was weak to CLD). This version of Futo is also very resistant to WND.
Affinities, ailment resistance and level aside, Abyssal Futo seems otherwise unchanged from her original incarnation. Between her slightly different stats and the progress you've made since B4F (the first version of Futo you fight is right before the Infinity Corridor and Awakening is made available), you shouldn't have too much trouble. At the very least, you have more options than "just Tenshi" for counteracting Futo's buffs.
Music is "Legend of the Great Gods" from Touhou 13
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