there's a npc summon just before you get to it, didn't bother with it on my previous attempts but decided to use it on my last attempt and pissed it, draws a lot of the agro and made it much easier
also you get a chalice for defeating it, not read anything about the game so had no idea what they are but you can use them to make procedurally generated dugeons, if it works then it's probably the best idea ever