I'll say this: I'm 90% satisfied with the magic system (don't ask about the remaining 10% :D). I don't care at all about the cost of spells. As for the Necromancer with the ability... well, the one that allows them to replenish mana when dealing damage, I, as a Necromancer, don't care; the main thing is that the Imps die, and that's just a matter of time...

Added 1 minute ago

In such cases, you should use teleportation.

Yeah, right into the mines! The new system with the option to choose the placement of mines won't save you