Creating unified inter-portal rules.

I suggest limiting the use of magic, at least by requiring the hero to have a corresponding level of Wisdom and a built Guild of Mages in the castle, regardless of the presence of any artifacts.

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Wouldn't this compromise lead to some players saving in autosave.gm2 before a risky battle, and if they lose, they'll say: "Oh, I didn't have enough time, let me load my file and finish it!!!"? And of course, they'll load the file where they saved before the attack.

If a person strives for a not entirely fair game, they will find a way to cheat anyway. IMHO. And this can be seen as a small trick within the rules.