A heavy mobile suit developed by Zonic as the next main mobile suit for space combat to replace MS-06. The origin of the development is the XMS-11, which was tentatively approved for the development of the new mobile suit that the Earth Federation Forces is deploying. The main purpose of the aircraft was to make it possible to carry beam weapons as the main armament, but at this point in time, a conversion design for space combat of the local warfare aircraft 09 Dom of the junior manufacturer was applied for. It was not possible to face the trial in perfect form (MS-06R-2, which was diverted and developed by the company, participated in the trial with some equipment for 11 type).
When the development of this unit was completed, the unit number was changed by the unit number integration order, and the unit was renamed MS-14. As with the previous trial, a selection competition with Zimmat's MS-15 was introduced. The MS-15, which was designed with an emphasis on fixed armaments, was rejected, and the MS-14 (formerly MS-11), which had been developed further, was given the common name GELGOOG. The main weapons were a beam rifle and a bidirectional deployable beam sword, and the portable external shield that had already been introduced in the MS-07 was adopted.
The first prototype was painted cream yellow visually and participated in various functional tests conducted at the Granada base. The feature of this machine was that the layout of the propulsion rocket engine was changed inside the waist skirt (auxiliary propulsion). The rocket was put together in a leg armor fairing) (the usefulness of the Type 09 layout was evaluated).
Given the model number of YMS-14 as an additional prototype, 25 were delivered to the Assault Mobile Army ahead of the mass-produced MS-14A, and the earliest completed aircraft was Kycilia Zabi. At the request of Maj. Gen. Zabi, he was sent to His Majesty Colonel Char Aznable. According to the military's jurisdiction record revealed in the postwar investigation, the colonel who was reassigned to the assault mobile army as a commander of a special experimental unit including MAN-08 type mobile armor has experience of engaging with a new aircraft of the Earth Federation Forces. It is said that he showed a stronger interest in the equipment of this completed aircraft than the MS-R09.