I've just spent 5 hours in SK, and came out with 6 Head of Shen. 4 hours was spent finding the PH, but once the PH was found the heads were rolling in. Other comments are saying 36s respawn on the PH. I don't know if that was correct in the past, but I do know that it is not correct today. It is a 30 second respawn. I timed it 20+ times, it was always 30 seconds. The problem is most of the trash in the field is also on a 30s respawn timer. So you can no longer use the respawn time to determine who the PH is.
Mobs that I have seen on Shaman Ren`Rex's spawn cycle (Grisok spawns immediately on Ren`Rex's death) include:
a bull elephant
a lioness
an elephant
an elephant calf
aviak egret
centaur archer
centaur charger
centaur courser
centaur sheltie
Kurrpok Splitpaw
There are likely more mobs in this cycle, but these are the ones that I saw until I got 6 heads and left. Every one of these mobs spawned in the south east quadrant of the zone. All south of the undead spire, and east of the splitpaw.
Edited, Aug 3rd 2024 8:33am by riguild