Necropolis and Demon.

That's exactly what I'm saying :) And they only seem tough when choosing their defenses. Yes! If you choose creatures up to Cerberuses, it's a complete mess. If it weren't for the gate opening, the demons would be in trouble. By the way, I can add here that elven troops are quite effective against demons. I hope that in the sixth installment, they won't change these magical archers, who manage to cut down a quarter of the enemy's troops before they even realize what's happening :D