A 4000 hp dot yay right but why on earth would you brave that for the crappy loot must be part of a quest as well or no one would ever kill it for this crappy loot.
75 monk, 75 ranger and 65 paladin had a run at this gal, self buffed only. The nuke hit me for 3600 right away on pulling and the dot finished me off. 75 monk fared no better while the 65 paladin heeded our advice to scoot and made it alive to Katta Castrum. I'd need a heal-over-time and a patch just to pull the darn thing, at least it seemed to be targeted and not an AE. She didn't hit very hard, but with a spell like that, she doesn't need to. My resist average is around 420 (not including corruption) unbuffed.
She spawned on the northeast part of the island, just inland of some undead sailors on the shore, in a little valley with a pool. Had to clear one undead sailor and two other sirens to pull her out onto the beach.