Heroes 4 castle siege mechanics
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After searching the internet, I cannot find the exact mechanics of castle siege in Heroes 4.
Browsing through some websites in English and Russian I have found that units on the towers get 100% increased attack and defense. Is this correct? Are there any other effects compared to the regular combat? Based on my experience I suspect that regular troops inside the castle walls (not on tower) also get certain bonuses? Is there a reference somewhere?
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Heroes of Might and Magic 4 - Easy Castle Siege
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Images: Davide De Giovanni, KITSUN YUEN, David Floyd, Paul Macallan