HotA - General Questions and Discussions

I've been analyzing this new restructuring for a while. One question (am I understanding correctly?): if you want to learn a spell that falls within a restructured sphere, i.e., a restructured spell, can you not restructure it afterward? This is, to put it mildly, not very good. P.S. Specifically for the mt-jebus template, my wish is: if possible, make it so that at least one castle with 5 gold mines is always generated on the starting map. That is, when starting as Barbarian/Swamp/Castle/Cove, at least one town is generated that is different from these 4 cities.