Combat System
From Heroes of Might and Magic: Olden Era Official Wiki
Combat in Heroes of Might and Magic take place on hexagonal battlefields. Your army starts on one side of the battlefield, opposite from the opposing army. The battle proceeds in rounds of combat, with unit stacks taking turns moving through the battlefield and attacking enemy units. One round consists of each unit in your army and the enemy's having had a chance to take a turn or use an ability.
Turn Order
The Attack (atk) increase the damage dealt, by multiplying the damage by 1+Attack/20.
The formula for the damage is : unit count * [random value in the attack interval] * (20 + attacker atk)/(20 + defender def)
The attack of the hero is added to the attack of the creatures under their command.


