At level 2, a Dark Elf of level 17 (!!!) with a considerable army, including dragons, appears. At what difficulty level do you suggest playing? Perhaps there is some feature that I haven't understood?

I tested it on Veteran difficulty.

I've released a new version 1.0.1. Changes:

1) The AI's development speed has been slowed down.
2) More neutral creatures have been added near the castle.
3) Spelling and description errors have been corrected.
4) After passing through the portal, the starting hero receives a small army.
5) A large amount of gold near the castle has been moved to another location.
6) The guards on the AI portals and bridges have been strengthened.