Heart of Chaos

There's a good strategy: quickly conquer all the Dark Elf cities, and then focus on the Demon. After defeating the Demon, you can build up your forces a bit and then go to crush Grol in Ur-Kurg. As for Dominion... you definitely need all the artifacts that increase initiative, and a lot of magic defense.

I just assembled a full set of gnome gear, got a ring with +20% initiative, the Staff of the Underworld, and the Cloak of Shadow Death. My skills are: Fire Protection with Blessing, Stone Skin with Solid Defense, Master of Curses, Sorcery, and the Rooster skill. I just stood in defense and blasted everyone with mass spells, occasionally charming Archdevils. With this setup, defeating Dominion turned out to be quite easy. Before that, I tried a build focused on Readiness, as well as another strategy with summoning a Phoenix to block my own creatures and using Banish, which deals... 2 damage. To prevent Irbet from capturing all my cities, I just chased her around the map with caravans, and then we met in the first city of the League, right after the garrison. I finished it in about 3 months and 3 weeks. I want to express my gratitude for such a high-quality scenario. The map looks very beautiful, especially the cliff where the Tome of Chaos is located. I would really like to see more of your work! P.S. I didn't complete any of the optional quests