I got this for my Iksar Shaman and was pleased with the stats as well as the looks. The skull on it looked like an Iksar skull. For the roleplay affect I would say my shaman was carrying the wisdom of his ancestors with him everywhere he went.
Got this item the other night when we were camping for the ribbon of empathy. Stats aren't the best and its got the rec. level, but it looks awesome! A shame they couldn't have made this one a little better stat wise. His area is near the golems, its down a dual spiral staircase and then from that room he spawns to the left ph is a diviner. The other warlock spawns in the room off to the right ph is also a diviner. Happy hunting :) <edit> As far as his rarity we had each warlock spawn twice in about 2.5 hours.