Seek out the manifested portal in the Coastal Grove of Antonica at ( -2323, -32, -758 ) /waypoint -2323.22, -31.79, -758.27 near the druid ring. This takes you to an instance called the Pantheon of the Prime Healer.
Speak to the Avatar of Health, who tells you to investigate rumors of Seeress Ealaynya Ithis's tomb being descrated.
Enter the Seeress's tomb in Antonica within sight of the gates to North Qeynos ( 137, -15, -193 ) /waypoint 137.10, -14.55, -193.09
In the area directly ahead of the zone-in you will find a follower of Anashti Sul who tells you that you are too late and the Seeress now answers to Anashti Sul. The follower despawns and you are attacked by Reanimated Seeress Ealaynya Ithis, a level 73^^^ heroic. You must lay her back to rest (kill her).
Return to the Avatar of Health and inform him of the unfortunate situation with the Seeress and receive your reward.