The castle is the main building in your town. Its level determines the maximum level of all other buildings.
There are a maximum of 34 upgrades available although currently you can only upgrade to level 33.
Each upgrade apart from level 7,18 and 34, alternates between raising the castles damage and hitpoints starting with a damage upgrade. Level 7 raises the drop chances for rare soul gems, level 18 for epic soul gems and level 34 for mystic soul gems.
Besides setting the maximum level of all other buildings the castle has no active role in the game.
Upgrade costs and benefits:
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