"HW rulez" mod (add-on) for HoMM3.

It seems like it was explained as follows: KSh prohibits magic during combat, while AoTD triggers before the last turn.

That's not true. AoTD triggers during combat and on the first turn. If you don't have the first initiative, the opponent moves first, and then AoTD triggers.

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There are just a lot of bugs in Heroes that are commonly considered features.