Added 27 minutes later
Yes, I can only win at the cost of irreplaceable losses. In essence, the enemy armies are not very large, and my Nura is not far behind in level, but the boosted artifacts and stats of the AI do their job + very bad random spellcasting. If I had a Phoenix/Resurrection, it would be more interesting. I'll probably have to replay, but now, knowing the map and the enemies (as I understand it, only Demons, T.E., and Gnomes will attack?), I can develop a winning strategy.