The Book of Covenant (colloquially, books) is an item which is required in order to upgrade the Castle. It is similar to the Arrow of Resistance, which is used to upgrade the Watchtower. Description Books can be obtained by defeating Barbarian Forts on the map, in the Shop, or purchased for 10 Gems each when attempting to upgrade the castle with insufficient books. Item Description Gained from Book of Covenant Can be used to upgrade the castle. Barbarian Fort Lv.1-4 (x3) Shop VIP Rank 2, 4, 6, 10, 13, and 14Special Privilege Chests (varies) Retrieved from "https://riseofkingdoms.fandom.com/wiki/Items/Book_of_Covenant?oldid=10051" Community content is available under CC-BY-SA unless otherwise noted.