See complete list here:
http://en.uesp.net/wiki/Online:Horror_of_Horrors
I answered on your previous thread. He spawns in arena, he does NOT spawn in temple. Here is a list:
Amoncrul — Nobles District
Baron Thirsk — Nobles District
Glorgoloch the Destroyer — Arena District
Immolator Charr — Temple District
King Khrogo — Arena District
Lady Malygda — Arboretum
Mazaluhad — Temple District
Nunatak — Memorial District
The Screeching Matron — Elven Gardens
Volghass — Memorial District
Ysenda Resplendent — Arboretum
Zoal the Ever-Wakeful — Elven Gardens