The safe spot mentioned below is the WSW (West Southwest) part of the wall in the circular room.
All mobs can be pulled to safe spot, after you break the room.
Only the ESE spawn can bring a chimera add. Just watch the pathing before you pull.
Use snare, they will run at low health to the path where the chimera patrol.
And my parses showed a 17min spawn rate from first aggro.
More observations from camping:
Balancer also pops in this room. Balancer only pops in the SW spot, near the safe spot camp.
If Balancer pops, you won't get Pyrilen Riftseeker or a Dragorn Battlemaster.
The north spawn point is for the Dragorn Battlemaster. If he pops, you don't get Pyrilen either.
You can get Balancer and the Dragorn on the same cycle.
Edited, Mar 25th 2013 3:43am by krogarEQ