Grimrock: Combat spells are almost universally available, with only slight variations depending on which mages were recruited to build the guild. The best ones are found in the Mage Guild building after it's constructed, including resurrection. The Mage Guild provides many benefits, including map teleports and good mercenaries, so it's beneficial not to leave it for last.

1) Follow the Demon path, i.e., obtain the Grail (Ash's Tear).
2) Collect several pieces (I collected 10) to determine the location.
3) Max out Ash's blessing.
4) Go to that location; it's a bit unusual, and dig up the tear (I think the author understands how I dug up the tear).
And after all these actions, nothing happens. I went back to the demon, and he didn't say anything. Is this a bug? What should I do with the tear?

I was wondering if anyone would take this perk or not. The quest can be completed in the usual way: collect enough obelisks, remove the tree with the demon, and the quest will automatically be completed. It's probably possible to fix the bug in future versions by adding the perk to the list of prohibited perks (I forgot to do this earlier).