A: The first Branch Fortress is available at Lv. 30, the second at Lv. 40, the third at Lv. 55, and the fourth at Lv. 70. A Branch Fortress can be of either economic or military type. Focused on battles, a Military Branch Fortress allows you to train more troops and increases your Generals' Power, provides faster speed in cross-realm battles, and raises the amount of resources plundered when attacking an enemy city. On the other hand, a production-centered Economic Branch Fortress allows you to build resource-generating buildings and buildings that speed up the production/collection rate, while enhancing city defense by allowing more Storehouses to be built.