Legend II - Fortress War, is based on classic castle sieges and large guild vs. guild battles. Basically, large alliances are waging war for total control of the fortress. The winners gain access to it, then defend it against other players in the future. They can raise taxes near the town that it's in, and make adjustments such as reinforcing the gates, adding more defenses and hiring NPC mercenaries for war.
Here are some Fortress War screenshots . More photos in the Silkroad Online Gallery.
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