A spirit chanter

Level 45 · Erudite Ghost · Cleric · Paineel

With a 55 enchanter, can be single pulled. Nearby mobs in other rooms will not assist. But this NPC is in the middle of a bunch of cleric GMs so you can expect tons of heals and to encounter this character fully buffed. Each cast of Dementia (625dd) took off about 8% of her health *after* she was dispelled. But kind of hard to see if she was buffed mid-fight or not.