"The Will of Ashan" - "Heart of Darkness" [2nd campaign, 5th mission]

Estel_Laiquacalma, you're amazing! Thank you, I probably couldn't pass it because I was missing one more Necromancer, but with your method:

See, it turned out not to be that difficult after all. I hope I helped, good luck, and feel free to ask if you need anything else))

Added 8 minutes later

I've only bought two heroes so far - I don't have enough money. I think buying a 3rd one is never too late.

What difficulty level are you playing on? I played on Veteran, and I didn't have any particular problems with finances, especially with having several castles. I think buying a third one is never too late, but I was describing how I passed it; everyone has their own tactics, although who knows, there can be glitches, we've all encountered them))