I don't know how you manage to play against the AI on 200% difficulty, but even though I've perfected my fast development strategy, I can't seem to outpace the AI. More often than not, I get attacked by hordes. For example... I have 12 Titans and about 30 Nagas, along with other units. Then a hero shows up, decked out in artifacts, and has 78 Archdevils and a support group gathered from different Castles, levels 5-7. Well, I defeated him (he ran away, and I didn't get any artifacts). Then a second hero arrives with a bunch of monsters, averaging 100-150 monsters per group, levels 3-5. Okay, I defeated them too. Then a third hero arrives with monsters of levels 1-3, in groups of 400-800. My army is already in tatters (I managed to save the Titans), and I lose. No matter how I experiment... If I combine all my units, he has 700 Troglodytes that he constantly revives, and I can't blind them, and I also run out of mana quickly. After sealing the breaches with force fields and other tactics, the AI still wins because the mana inevitably runs out. If I conserve mana, I lose even faster because the Blind spell only lasts for 16 rounds, which isn't enough for me. I tried simply using a force field to protect the Titans, but the force field breaks, and the Titan slowly and painfully dies when the charges run out. And the force field itself isn't very good, it only lasts for 6-7 turns. If I start with a Ballista, the AI immediately switches to Earthquake, and that's it. Plus, he has Gargoyles and Harpies, which I have a lot of trouble with (he turns out to be an Earth expert). P.S. I didn't have Berserk at that time. And, in general, it often turns out that I can't get the spell I need. I still haven't figured out how the AI organizes these attacks, but it works surprisingly effectively. I'm forced to stay in my Castle and not move more than 2-3 turns away from it. Then the AI's power slowly grows, and it overwhelms me with numbers. At this point, nothing helps, even though I was already level 37 with a hero who had survived countless attacks and retaken the Castle 7-8 times in the game. Hero Solmyr, attack 14, defense 11, Knowledge 27, magic power 21. Skills: all elemental magic, wisdom, witchcraft, intelligence, and tactics.

Added 19 minutes ago
P.S. A favorite tactic is Blind, then use Destruction Ray to reduce the monster's defense to 0. With such low defense, even a Lizardman will be sent to the afterlife almost immediately (if you have the Amulet of Vulnerability or the Sphere of Vulnerability, I don't remember exactly). I also often use Berserk. In general, attacking spells quickly become irrelevant when the number of troops exceeds thousands, so Blessing is definitely useful for Nagas and Titans (if they are not experts, of course). They have a large damage range. I love Forgetfulness and Curse, and I don't even need to mention Haste and Slow. The most powerful thing is Clone on Archangels, especially if you have more than 15 of them... and even more so when you have several hundred. Each clone can revive... in my opinion, this is complete cheating. With the Clone spell, a Water Magic expert, enough mana, and about a hundred Archangels, I could defeat giant armies that were hundreds of times stronger than mine.