Walkthroughs for custom maps.

Of course, I can’t know what the AI is “thinking” or why it casts spells in some cases that aren’t immediately obvious, but with enemy heroes, I often try to blind their last remaining stack (it just needs to be without immunity!): if the resistance doesn’t work, then after that, the “opponent is completely under my control.” :) If you blind a strong stack in advance, especially the main attacking one, the enemy won’t put up with it and will come up with something.
With neutrals, of course, it’s easier, unless there are wizards or master djinns among them.