Renvard
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Download "FizMiG" (an unofficial guide for "Heroes 3"): it contains a lot of useful information! One of the older versions (2.3), which isn't too bulky and isn't overloaded with unnecessary information: https://cloud.mail.ru/public/7Ydg/nK9uUBKdK
The difference lies in the starting amount of resources, but not only that.
This is described in detail in chapter 7.10 "Start of the game, AI, starting resources, and the Penalty option."
We were talking about a completely different level of difficulty, and the comment below you gave the correct answer. But still, thank you, I didn't know about this guide and now I understand why the bot didn't buy more heroes on some maps.
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