Any champ spawn (other that the psuedo-spawn in the labyrinth)
Fel Spawns give 0.6 to 1.0 scrolls
All other facets' spawns give 0.1 to 0.5 scrolls.
they drop at half the rates of 105 scrolls (as they use that system's trigger), though that rate will be higher in the non-fel spawns with the next publish (Fel will be 50% 105/50% SoT, others will be 100% SoT - currently it's the 50/50 rate on all facets, with the result of a 105 being no drop outside Fel). It would take 8 average Non-Fel scrolls for a skill to be advanced the same amount as 3 average Fel ones, so the Fel spawns would still have a 33% advantage even with the non-Fel rate for the small ones doubled, before factioring in the amount of creatures AT the Fel spawns is higher, leading to more kills, and therefore more chances for SoT drops.