First ph is on the first floor, it's pretty obvious. Second ph is on the upper floor, and you have to go outside the building and up a tentacle through a broken wall to access that floor (ramp is broken).
My box of 104-105 toons had little trouble with this named. I didn't even bother to stay out of ae range. "Decrease Hitpoints by 100000" SOUNDS bad but it's highly mitigated. I was all ready to chain-cast group heals with my druid but my toons never dropped more than 20% each time he casted Fracturing and I ended up only needing to cast Luna 2x, and even then just to be safe.
Dropped Median essence, dactyl dagger and highwater bracer. Too bad, really wanted Geomantic Steelstone...