This twenty-year-old museum piece was the first military mobile suit, and is the common ancestor of both the Gundams and Oz's own mobile suits. Oz deemed the prototype Tallgeese too expensive to mass-produce and too hard to pilot, so the design was simplified and scaled down to create the standard Leo. As a result, the Tallgeese's specifications are superior to those of most modern mobile suits, and this mothballed prototype is the only thing in Oz's arsenal capable of fighting a Gundam. However, its high acceleration and instability make flying the Tallgeese hazardous for even the best of pilots.