Go to Starcrest Commune and use the undead portals to pierce the veil and remove the undead anchors. You may want to clear part of the zone first to cut the number of possible adds down.
Click a portal (the new ones, with whispy skeletons rising, not the old ones, for example at 713, -19, 280 .
Your vision will turn purple and you will be able to see the anchor on the ground. Click it, kill the mob that spawns, then click the portal again.
719, -20, 281
736, -24, 336
735, -20, 279
752, -20, 243
772, -20, 240
797, -19, 248
787, -19, 295
768, -19, 284
762, -20, 270
799, -20, 301
790, -25, 328
778, -24, 342
760, -24, 332
When you remove the final portal you'll be attacked. Do not kill the adds, they will heal the main mob. You need to stay close to the mob when the bubbles spawn and retreat when they explode. It will damage the mob but not you if you do it that way.
Finish removing the final anchor.
Return to Crexisz.
Speak to Felion Shadoweater, who is up the blue teleport at 713, 35, 138 . Place the void anchors on the ground at his feet.
Return to Bellengere.
Drama ensues.
Bellengere will banish you from the tower and teleport you to the moat.
