The Fortress Prototype is the first Floating Fortress encountered in BTD7. It appears as a flying fortress being built with signs saying "UNDER CONSTRUCTION" around it, with 4 ZOMGs in it's bays, which are it's children. However, despite looking like a ZOMG Carrier at first glance, it actually has some abilities. It is half the speed of a ZOMG, the same speed as a B.O.S.S.. It also takes 10000 hits to destroy. It first appears on round 110. Also moves slower when reaching 2000, 4000, 6000, and 8000 HP for the core. It is also double the size of a Z.O.M.G..