Comments posted to our Dark Souls 2 Wiki
The Lucatiel summon and magic resin makes this fight a breeze. Lucatiel is a damage sponge. All you need to do is dodge a few attacks until the demon aggros on the phantom and cowardly swing a few times into its backside and retreat while you recover stamina. Demon was beating on her mercilessly and I never saw her health drop below half.
The run-up to it is pretty tedious, but the fight itself is one of the better ones I've had in this game. It starts slow, just so you get to know its moveset, and it builds up as you keep fighting it. It punishes turtling enough as to incentivate you enough to know its moveset, and after that it becomes a matter of timely dodging (although the big overhead smash is tricky to get used to, and I got hit by the first horizontal swipe a whole buncha times). It gives enough window for you to heal, particularly after the jumping attack, and that window gets bigger the longer the fight goes on. He kicked my *** a whole bunch of times, but I have to admit, this has probably been the best straight-on boss fight I've had so far in the game.