Picked up Avernum again recently and had a thought after spending the day gardening in Real Life: What if someone created an artificial sun in Avernum? How hard would it have been? Magic seems commonplace enough and has the power to create barriers and traps and such. It wouldn't have to even be a sun, you could just artificial lighting through a string of fireballs or something that give out enough light for several hours a day to grow crops. Perhaps it may even be powered by the cave's natural heat or some such. (Though now that I mention it, I do recall it being said that the plants are modified to use the cave's heat instead of sunlight so I guess that's a more direct approach)