Revenge !

Some thoughts:

This bossfight's main difficulty comes from the infamous 3 slash combo, on top of making me paranoid, this ruined the large majority of my attempts and forced me to switch to a Talisman enhancing backstep.
The addition of light pillars on this move during the 2nd phase makes things even more problematic, requiring the backstep to be done earlier, making the timing unreasonably tight, or to preventively run to the left every time he could do it (I opted for this solution).
Unfortunatly (or fortunatly for me) this run doesn't feature this cursed move.

This move aside, the bossfight is very enjoyable and could be one of the best FromSoft designed, the mixed timings, the little optimization that a lot of his moves allows makes it a truly fun fight.

I tested the Quality Infusion with 99 in both STR and DEX, but the damage was kinda disappointing, a Frost or Bleed ailment seems mandatory on this weapon, this will be especially true on later NG+ cycles.

The build:
NG+1
Scadutree Blessing (20)
VIG 10| MIN 13 | END 40 | STR 75 | DEX 75 | INT 70 | FAI 15 | ARC 9

Weapon : Dane's Footwork (Ice)
Ash of War : Dryleaf Whirlwind

Talismans :
Blue Dancer Charm
Shattered Stone
Ritual Sword
Talisman of All Crucibles