Last skirmisher. Auto-translated

An impassable garrison consists of 999 dragons (immune to dark magic spells) and three groups of 999 archers and elf wizards of two types each. After visiting the Jarl, the garrison does not disappear.

Added 2 minutes later
Yes, and "astral gates" do not appear in the spellbook. Strange questions, just play through the map and you'll see everything for yourself.

Well, the garrison is easily defeated. You can watch a walkthrough of the Remix; the main focus is on the Dungeon faction. There is a mentor at the end, and you can change the skill progression.

The map is interesting, but not very challenging. Perhaps it would be worth making the gameplay more difficult?

I played through the map. Overall, I enjoyed it: the design and the plot are at a good level. I encountered the bugs that have already been described: after destroying the orange castle, the quest to unite the clans is not marked as completed (or is this quest about something else?). There is a very annoying bug with the arena where they give out harpies. If an AI hero reaches the point first, it starts frantically attacking it, and the player receives five to ten messages about fighting the guards – you can't dismiss them. You can fight the arena guards, even multiple times, but the harpies will be given to the AI hero. I cannot confirm the bug with clearing the mine of undead. The script always worked correctly, regardless of whether you received the quest first and then went to the mine, or vice versa – you cleared the guards and then went to the hut. I don't understand the situation with the totems. After all the manipulations, I read the inscription "Behold...", and the yellow garrison is highlighted. So what? What is the point of such a complex structure for the mage's eye? (This elaborate ritual has nothing to do with the ability to attack the garrison or the number of guards). I cleared the garrison with a few rogues using "Summon," nothing special. The final battle: "chaos" with "Summon." The tips on using "Darkness" are good, but only when you have spells that counter it. The map does not end with a victory over the yellow player. So, it is impossible to complete it fairly. This serious flaw in the map has not been fixed yet. I didn't like the location chosen for the mentor, so I didn't use it.
The increase in neutral creatures could have been made stronger. After obtaining two castles, a large army accumulates, and to defeat all the regular neutral creatures, ten rogues are enough.

Yeah... I always read the comments before playing, and it's worth it. As for Nike... it's not right to just abandon maps like that. She should at least post an update saying the map has been fixed, or the moderators should delete it and clean up the mess!