In search of the Rune Sphere.

I completed the map in 6 months using a single hero. Here's how it went: Vittorio. The first battles were tough, but after I captured the Ring of the Machines and found the Fire Arrows, all battles, except against the dwarves near the catapults, became easy.
Edward. On the third week, Faidaen visited me. The battle with him would have been easier if not for the Berserk spell he got from a scroll. Then, Gilraen arrived with a decent army, and Brand also arrived with a decent army. I took the Elven Castle, losing 2 Archangels (I defeated the entire army thanks to the hero's special ability and regeneration). After capturing the Dwarven town, I sailed to Grimheim. I liked that the dwarves don't focus all their attacks on one unit, which made the battles with them (except against Karli) interesting. The battle with Hanwul wasn't entirely fair. When he moves, he summons a Phoenix and Fire Elementals. I lost many troops, but I didn't replay the battle. In the final battle, Tolgar destroyed all my troops with Divine Retribution. Only the horses remained. I cast Antimagic on them and applied various buffs, then defeated the remaining dragons. I was lucky enough to see the final cutscene.
Now, the downsides (or rather, just one downside): it's good that artifacts aren't automatically taken from the dwarves after victory, but Ibba stole the Crown of Sar-Issa, and it wasn't available in the artifact shop.
I have no other complaints.