|This article is a Stub and is incomplete.|
There is no running around needed, after entering the zone, just stay to the right and when you see a series of rocks just before a two person mob, jump up and your at the end boss!! Kill all the minions first then attack the boss. Minions will spawn when the Boss gets to about 1/2 health, and they hit HARD!! Finish off the boss then get the quest item and your done. Easy.
Update (Spoiler): Perhaps this used to work, but I had a completely different experience: Proceed into the cave, killing for good experience. When you reach the second blood pool, turn sharply back to your right, entering a tunnel containing Animated Canines. Barely pass through the next blood pool's chamber, then turn back around to your left, through the passageway of the Ancient Ghouls. After winding around a bit, you come to the first boss, the Collector. You must kill him and take his key. He will come when you attack his dogs, so expect him. Return to the previous blood pool. Kill the lizards and dive in, swim deep, then swim toward the light. You'll surface in a secret chamber with a rusty gate, which opens since you have the key. You'll be confronted with another pool. Again you must swim. Swim to the right, then surface. You arrive in the final chamber. You'll be shown a quick cutscene illustrating that the Phoenix of the East is present in a small chamber beyond. Har-Shebesh, level 60 boss, is here, surrounded by 6 level 60 liches. It is possible to clear them before fighting Har-Shebesh. He has a protective spell that appears as blood streaming towards him. It lasts about a minute, during which I was unable to hit him, but eventually it ended and he could be hit again and finished off. Don't forget to go get the Phoenix!!!
The walkthrough is ok, save the part about the final boss. The minions have to be killed before you can harm the boss. In order to kill the minions be on the lookout for glowing spheres to appear above them (they also get bigger). Always target the big one because otherwise not only they reappear but you become rooted for several seconds. Once you are done with half (four) the boss will start area attack spells with spikes coming out of the ground. At that point start harming the boss. Once he is around 20%-25% health you need to kill off the rest of the entourage (four more minions). When they are gone proceed to finish off the boss and claim the amulet piece.
p.s.: An easy way to pick off the minions is to hide behind the rock formations every time your health is low. The minions stay dead while you regen. This goes for the boss too. While you play hide and seek with the minions (2nd round) his health stays at that 20%-25%.