Hooray, I'm going to beat this map!
Added 10 minutes ago
I finished it. Actually, the scenario isn't that difficult. I just temporarily gave all the demonic cities away, and cleared out the Dark Elf, after which I triumphantly returned to the surface. Powerful artifacts from the start and a useful specialization allow you to tear through enemies left and right. The ballista under the Ring of Kinship with machines also helps. As a result, even logistics weren't needed. Oh yeah, when I had already cleared the map, heroes started appearing in the tavern. By the end, I even collected a complete set of available heroes. The only thing is, I wasted my time leveling up Darkness, because in the end I only used it a little in the finale through the Tome of Darkness. I should have leveled up Logistics instead. It would have been easier with that.
Now, for everything else.
1) The concept itself. The mission reminded me a lot of a map by IchGVij, only easier and with Dark Elves. There isn't much originality in it.
2) The plot. There have already been many escapes from some location. And the characters are too fond of quoting lines from the original game, which makes me feel like I'm playing Agrael, just like in that same scenario by IchGVij. It's unclear why this was done.
3) The finale. The final boss is very over-buffed, which doesn't really help him, because my army was very powerful by the time I cleared the map. However, if you rush to take out the demon's capital (which doesn't make sense, because after capturing all the cities before it, the enemy stops buying heroes), you can't avoid meeting the Dominion. They teleport you there by force) This is quite amusing, because Groll himself is weak and can be defeated quickly. Especially compared to the Chaos Knight in the Dark Elf capital.
4) The demon, for defeating whom you get a lot of stats. Only Chaos can talk to him. There are no dialogue options for the other heroes.
5) The reward from the dragon is quite amusing, because at that point I was wearing the best artifacts, and parts of the dragon set had dropped from Sigrif and from the Dragon Utopia.
No bugs were found. Oh yeah, that's a real achievement)
The map is quite fun, which is a good thing. Overall, it's quite good in its current state. However, the plot is very weak. If the previous map suffered from its presentation, then it's better here, but the essence of the conflict is too banal. This also reminds me of a map by IchGVij, but for some reason I paid less attention to it there.
I don't recommend making the map more difficult or giving Groll over-the-top stats, like the bosses in the previous map.
Thank you for the walkthrough. It's great that there are no bugs. The scenario is indeed similar to a scenario by IchGVij, but the plot is completely different here, and besides, it's just a prelude to the next events.
I came up with the quests as best I could. I didn't know that they would all be ignored, and you missed out on a lot of buffs from the Devil and from the Prophet (the first reduces Attack on enemy demons by -7, Luck by -3, and Defense by -5, and at the beginning of the battle, Devastating Ray, Plague, and Slow are cast on all enemy units. From the Prophet, in addition to 20 Death Knights, you can get a bonus - choose one of 4 spells, and it will be cast at the beginning of each battle).
Regarding the over-buffed Dominion - originally he was a MEGA-boss. He had a lot of health, and combined with the spells, he became invincible.