BTW..ya don't need a raid to get to the chest room, its the first room in the castle.
Group had 62 monk, 61 war, 65 cleric, 58 druid, 56 mage, and a 63 enchanter.
Mob had a ton of HP, about 3x what a normal mob had. War had kept losing aggro to druid, but quickly ragained it. Once mob was slowed, no problem at all. A bit harder to slow than a regular mob.
You were over-powered. With a group of 61 MAG, 61 NEC, 61 CLR, we took this guy down once and then moved on. It just happened to be up (usually you get the PH which is a false treasure chest), so we killed it on our way to the rooms at the end of the hallway to the right (where we found an entire guild's worth of corpses, presumably from a failed raid in the higher end areas).
I think a full group of mid-high 50s could easily take this mob down, and it's a nice tunic for those levels. As it was, we broght in an alt drood and had him loot it for CR gear.
We've never gotten the tunic again, just the pauldrons (which our CLR now wears, I think).
its not a common drop we killed it 4 times and it had nothing but pp there are also several KoS mobs in the room that were never there before including clever spinx and gorila scholar.