The big ones that come to mind are void-related things (like you said) and Black Magic. Considering Black and White Magic nearly killed the planet during the War of the Magi and resulted in the Elementals causing a massive flood... people aren't too happy with the idea of Black Mages being around. White Magic is also supposed to be under the control of the Padjali at the moment, so trying to delve into that without their permission might get them after you?
And, on a lesser degree of destructive power, the people of Sharlayan are very insular when it comes to the knowledge they have that could be weaponized. The AST quest line delves heavily into that, with the nation sending people after your Astrologian trainer because she's teaching the more combat-oriented Sharlayan style of Astrology. So anything war-related from Sharlayan is basically forbidden to outsiders from their standpoint.
Hope that helps!
And, on a lesser degree of destructive power, the people of Sharlayan are very insular when it comes to the knowledge they have that could be weaponized. The AST quest line delves heavily into that, with the nation sending people after your Astrologian trainer because she's teaching the more combat-oriented Sharlayan style of Astrology. So anything war-related from Sharlayan is basically forbidden to outsiders from their standpoint.
Hope that helps!
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