mages versus orcs

The problem is that you might not be able to create artifacts, and you might run out of resources, which depends on how long the game lasts. Also, the faction leader and the hero have a great ability that speeds up the turn. Therefore, the centaurs will move several times, and with Wrath of Blood, they will cut down any stacks of mages, and even a well-developed ballista with fire arrows won't let you relax. The mage can be saved by Darkness, or Chaos with Pyromancy. Well, it also depends on the artifacts and spells. A Hagga at level 25+ is overpowered. I have a friend who only plays as an Orc, and nothing else. So I know that Orcs are very difficult to defeat. In general, you need to take units with high initiative and use Darkness or a very strong Chaos.

Chaos against a late-game Orc? Are you serious? Darkness, yes, with the Wizard's Mark, you can blind two squads at once or apply Berserk to two squads at once. Grem and Minotaur will still move first and attack the centaurs. Taking out a Grem with a Minotaur with 10 HP, 10 defense, and 40% initiative is a problem even for an Orc. 1000 Grems with 18 HP is 18,000 HP + insane defense, which will halve the damage. And if it's Razzak with infinite golem resistance and a sudden teleport of that golem? Wrath of the Horde will hit 15 Titans, but who cares in the late game when you have 50 or more?
The longer the game lasts, the less chance the Orc has. He can definitely rush the academic, but winning in the late game is questionable. By that time, there will be enough knowledge and resources for Minotaurs.