Future king.

Respect to the map author! For a first map, it's very good! But I would like to express my comments.
1) Perhaps the map's balance should be reconsidered? Let me explain what I mean: it seems that everything depends on which army Sinithar emerges with. If it's a playable army, then everything is fine, but I had two instances where it was almost a disaster (army losses of 50-70%), and that was in the best-case scenario.
The same goes for the quest artifact at the beginning of the game - defending it with such losses is almost a Pyrrhic victory.
2) This problem has been encountered on maps before - the mentor is located in a strange place. Why put him in the dungeon and near the red castle? I suggest moving the mentor from the dungeon to the castle in the southeast (there's a similar feature on the map from Heroes of Ashan: Antares - the mentor is located in the lands of the mages, where he's needed like a rabbit needs a stop sign).
3) Regarding the artifacts - at the beginning of the game, you want to take something, but losses are inevitable. However, later on, you can equip all the artifacts you've taken to your companions. If the author's intention is to collect composite artifacts (Lion, Dragon, etc.), then again, it's very difficult to do at the beginning of the game, but later on...
Overall, the map is good - there are opportunities for various hero upgrades and gameplay. I sincerely wish the author success and look forward to more creations!