Awakening of Evil

It's impossible to remove spells from a hero using scripts, so there's no bug. I hope all the spells are level 3 or lower?

Yeah, that's right. But it's a bit boring to have almost all the necessary Dark Magic spells (especially the area slow, area dispel, area destructive ray, weaken, and vulnerability) available right at the beginning of the game.
And that's at the maximum level of Dark Magic.
I've only just started the labyrinth, but it's all there already.
It's impossible to have higher levels because there's nowhere to learn spells higher than level 3 in the first town, the castles only offer spells up to level 3, and there are no spellbooks or utopias that grant spells.