Developing an Inferno mage hero.

Sacrifice, combined with fire spells and "harass," is essential for an infernomancer. The infernomancer deals direct fire damage. And the 2-turn cooldown of the fire arrow kind of hints at that.

In principle, the scheme is simple.
First 3 levels - education, fire arrow, logistics. If you're only fighting with the hero's starting army, take fire arrow first. If you have a lot of troops at the beginning, you can start with education. At level 4, we don't improve a skill, and at level 5, we immediately take harass and sacrifice. In principle, at level 6, you can take regeneration, and that's it; you don't need to spend any more skill points to clear the map, and the hero will still be combat-ready. And save all the skill points until level 15 and then invest them based on the specific opponent if you're playing against a human. Or invest in whatever you want; you can't ruin the hero anymore. :)

Only the mage will be bloodthirsty, not tearful. :)

Added 19 minutes later

1) I noticed that a hero with "Pathfinding" spends movement points suspiciously quickly. I decided to compare it with a hero without this skill, and to my great surprise, I realized that this skill reduces the movement range on rough terrain. Since then, I've checked it repeatedly - the bug hasn't disappeared. People say that this bug has been known for a long time.

How did you check? The movement range decreases simply when loading a save.