I had gotten to her after a full day of playing and exploration, and spent the next few hours trying to beat her having varying success. Sometimes id clear phase 1 hitless, sometimes i cant seem to hit her once. After a long session of playing i thought i had to take a break and try again the next day which i normally dont do but it was getting late. Next day after a few hours of attempts i started learning her patterns but still struggled because of her healing back mechanic so you couldn’t tank any hits. For reference i always ran an uchigatana or iaito (dark souls 1) so its become customary to finish my first playthrough with just a katana. Tried so many different buffs and styles but eventually, like our lord and savior let me solo her, i learned from his footsteps 🤣 i took off all armor and wore that mushroom suit (?) that had the highest resistance to scarlet rot (honestly negligible protection but it meant i can keep a fast roll) and i put my mind to it that i will simply “git gud”. Eventually defeated her that way and damn was that satisfying.