The strongest castle in Heroes of Might and Magic IV.

Thank you for the clarification.
But I still disagree with that position. Chaos has many prospects. To build up a town, the Castle has resource gatherers: thieves and scout heroes.
Magic is universal. But it's still not the absolute best.

On small maps, Chaos has some advantages in terms of magic. For instance, Lightning can take out a lot of people, including heroes. But if you take substantial armies led by a mage hero who has been pumped up in magic to the limit, Chaos finds itself in a less-than-ideal position. Even Disintegration with damage around 2000 will no longer cause significant harm to an army. One of the indisputable pluses of Chaos at high levels is actually non-combat—the cloud of confusion. Cat's reflexes and the General first strike are also very good. This is an unconditional advantage for Chaos mages.