HP - 35-37k
DAMAGE - 40k with force weapon. (I use templar)
RESISTS - 475 average on all
Arcane Orb - Tap the Source
Diamond Skin - Crystallized Skin
Shock Pulse - Piercing Orb
Energy Armor - Force Armor
The Phasebeasts aren't hard to kill, its their ability to phase and whack the crap out of me. Is there another defensive move geared toward this part of act 3 (Tower of the Damned Level 2)? Between them and the Soul Lashers, I'm about to break something.
Unless you're built defensively with massive resists/hp, there's really not much you can do about the phase beasts and soul lickers. Just die a lot. My wizard got over 40k hp and ~900 resists all, and they even hurt me real bad. Those last few levels of act 3 really contains some of the toughest enemies in the game.
After several incredibly frustrating attempts going through the Arreat Core, I found that the easiest way to deal with them is drop diamond skin pick up Mirror Image/Duplicates/Illusionist. When you see them comming for you pop your images so they do their teleport insta-gib to an image instead of you. If somethig hits you it'll reset your images again. Spam images and kite around them and your hydra. Hope they don't pick you when they phase.
If I get camped when zoning in, I just remake game. Usually takes a lot less time clearing to the same point again then trying to beat them. And like some people have said, mirrors are best vs phase beasts while undergeared.
Try diamond skin + tele wormhole + illuisonist + force armor - it should get you through the place in no time if thats all your after.