Darkened Sleeves of Treachery (one out of five kills). (Not currently in the Alla data base. Slot Arms, AC 12, DEX 6, STA 4, WIS 8, HP 45, Mana 40, Fire 10, Cold 10, DRU/MNK/BL, Wt. 1.1, Rec level of 56 Slot 1 Type 7.)
This mob is located at /loc -487, +356, +14 in the tier 3 area of Plane of Hate. He was LB to level 75, and liklely level 63 as other Tier 3 mini bosses are level 63. He saw invis the two times I checked. He looked like a silk class PoH Tier 3 Dark Elf. He was present on track shortly after the server popped. He repopped twice more on clearing his room about six more times. He was an easy solo fight for a level 75 ranger even with his roommate as an obligatory add. He spent about half of his time casting necro (I think) spells, most or all of which I resisted. He is in a room with one other mob. The other two rooms in the building had one mob each, which did not add when I engaged Warlock J`Rath at his spawn site.
He dropped the Concordance of Black Magic once, the Book of the Dead twice, and Dread Silk Cap (tribute 8+K) every time.
In his excellent discussion of the Marsinger Gem Quest, Frackus Everburning (contained in his article Plane of Hate (b) (http://www.guildseofon.com/raidinghate.html)) a different mob is shown as being at this spawn site, Warlord E`Prosia). I would guess Warlord E`Prosia has moved to another site, as the room mate in Warlock J`Rath's room was a variable tier 3 mob, and therefore it is unlikely the Warlord and Warlord are unlikely roommates.