A tactical weapon mobile suit that constantly repainted the battlefield in the so-called One Year War over the independence of the Principality of Zeon. This humanoid mobile weapon has proved its usefulness in every aspect. The discovery of the Minovsky particles has turned old-fashioned weapon systems, especially electron-guided weapons, into useless long-lived weapons, pulling them back into the Mesozoic era of visible combat. Long-range, remote-controlled precision attacks became impossible. This drove the rise of Zeon in World War II. A new mobile weapon mobile suit that excels in aviation force, attack power more than ships, and defense power more than main ground vehicles in visible combat under Minovsky particle spraying. Not only was it possible to use large firearms, but it also demonstrated its ability as a general-purpose heavy machine capable of all kinds of work, construction, and work by taking advantage of its humanoid shape. However, due to the stalemate of the battle, even those that brought a great advantage to the beginning of the battle, it became difficult to continue to control the surface instead of the point due to the difference in national power. In order to overcome such a situation, the Earth Federation Forces newly developed a group of mobile suits called the RX series as mobile suits for mobile suits. The RX-75 large combat vehicle for long-range support, the medium-range support type RX-77, the first humanoid mobile suit, and the last developed was the RX-78, commonly known as Gundam. Moreover, these mobile suits have a stand-alone maneuvering center called the core block system, which makes it possible to replace the equipment that makes up the aircraft, and the emphasis was also placed on the recovery and protection of pilots. The implications of this groundbreaking replacement system have made a decisive difference from the mass-produced Zeon mobile suits. As long as the core block works, it is now possible to use the mobile suit in continuous combat semi-permanently. In particular, the RX-78, which was developed at the final stage, is an aircraft specialized for combat against mobile suits, and it is devoted to the exchangeability of exhausted combat and defensive weapons, and various options are prepared for the firearms used. Above all, the Principality of Zeon's army has taken the lead in carrying the beam rifle, which had been difficult to develop for miniaturization. The reason why we were able to make a thorough shift to these operations is that by refining the Luna-Titanium alloy (later completed as the Gundarium Alpha alloy), we were able to complete a lightweight and tough aircraft without daring to make it heavy. Throughout the One Year War, the RX-78 was completed as the strongest tactical weapon through three major phases. It can be said that the RX-78-2 type, which can be said to be the second stage of development, was completed by Dr. Tem Ray, the chief of development and design. Moreover, with the manifestation of the new type ability of Ensign Amuro Ray of the 13th Independent Force who became the full-time pilot of the aircraft, the aircraft became a magnet coating specification (RX-78-3) by Dr. Mosque Han, and the one year war period It was completed as the best mobile suit among them. In fact, due to the core block system mentioned above, the RX-78-2 type that participated in the actual battle became an example of utilizing the replacement system, and when the spare parts prepared at the time of the announcement of Operation V and later replenished by the ground troops Also, many 78-specification parts have been introduced. It is said that only a part of the data box equipped with Amuro's core fighter, which accumulated and recorded various actual battle phases, was suitable for repair, and the actual machine itself disappeared in the A Baoa Qu strategy, but after the Earth descent operation It is said that the data at that time was collected in Jaburo and the data after the Solomon Fortress capture battle was collected in Lunatu and used for programming RGM-7.