Heroes 4 castle siege mechanics

Heroes 4 castle siege mechanics - Aerial view of medieval fortress on green seashore

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?






Pictures about "Heroes 4 castle siege mechanics"

Heroes 4 castle siege mechanics - Marble statue with spear and sword on pedestal on corner of Fishermans Bastion complex in Budapest
Heroes 4 castle siege mechanics - Schloss Buckeburg Castle in Buckeburg, Germany
Heroes 4 castle siege mechanics - Clock Tower and City Hall in London





Heroes of Might and Magic 4 - Easy Castle Siege




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