SD Gundam Ex-Standard GN-0000 00 Gundam

The GN-0000 00 Gundam (aka 00 Gundam, 00 (pronounced "Double-Oh")) is the titular mobile suit of Mobile Suit Gundam 00. It is the successor of the GN-001 Gundam Exia and is piloted by Setsuna F. Seiei.

The GN-0000 00 Gundam was one of the new Gundams developed by Celestial Being after the paramilitary organization was defeated by the UN Forces in AD 2308. It was made specifically for Setsuna F. Seiei, thus it was designed based on his previous mobile suit, the GN-001 Gundam Exia, and reflected Exia’s performance data. Although Setsuna's whereabouts were unknown at the time of the 00's development, his Celestial Being comrades continued developing the mobile suit as they believed he would return. Deployed in AD 2312 following Setsuna's return and as Celestial Being made a comeback after four years of silence, the 00's most prominent feature is the Twin Drive System that utilized two original GN Drives. By synchronizing the two GN Drives, the Twin Drive System causes the resulting GN Particle output to be squared that of a single GN Drive rather than merely doubled. With this immense amount of GN Particles, the 00 was expected to have exceptional combat capabilities. The theory behind the Twin Drive System was developed by the founder of Celestial Being, Aeolia Schenberg, and hidden in the quantum processing system Veda. This theory was eventually sent to Celestial Being at the same time as the Trans-Am System.

The 00 was the first mobile suit to incorporate the Twin Drive System. Unfortunately, synchronization of the two GN Drives was extremely difficult, and this made achieving stable operation of the system elusive. Even with the use of GN Drives from the Exia and the GN-000 0 Gundam, a combination which had the highest synchronization rate among the five GN Drives that existed at that point of time, the system failed to reach the stable operational range. In the end, Setsuna used the Trans-Am System briefly to forcibly pushed the Twin Drive System into the stable operational range. This was a dangerous method however, as it could cause the GN Drives to overload and even explode. Although the Twin Drive System was successfully activated, the 00 was still incapable of stabilizing the system by itself, as demonstrated when both of its GN Drives overloaded during the battle with the GNX-704T/AC Ahead Sakigake due to use of the Trans-Am System. These problems were later solved by combining 00 with a dedicated support machine, the GNR-010 0 Raiser, forming the GN-0000+GNR-010 00 Raiser. Through this combination, the 0 Raiser's particle control equipment was able to control and stabilize the 00's Twin Drive System, and the Trans-Am System could also be utilized safely.

Located off the shoulders, the pair of GN Drives were mounted separately on two drive bases that were connected to the 00's backpack through a pair of drive arms. The drive bases could rotate to the front and back of the mobile suit, enabling the GN Drives to change freely from their standard side-facing position to other positions. This granted the 00 superior mobility as the GN Drives were covered with a thruster cone that enabled them to function as the mobile suit's main thrusters by emitting GN Particles to generate thrust. Furthermore, when the GN Drives faced the front, the emitted particles could be used to generate a GN Field for defense. The placement of 00's GN Drives was based on the operational data of the GN-XXX Gundam Rasiel, which had high mobility thanks to its shoulder-mounted GN Verniers. Due to the miniaturization of devices such as stabilizers that control the GN Drives' core units, the 00's GN Drives are smaller compared to those of the Exia and the other 3rd generation Gundams. As for the GN Drives' thruster cone, it was based on that of the 3rd generation Gundams' and incorporated functionalities of the three-thrusters type GN Drive cover used by the 2nd generation Gundams, such as the GNY-001 Gundam Astraea. Besides the GN Drives, the 00's backpack could also generate thrust using GN Particles due to a pair of built-in thrusters.

The Gundams were equipped with special antennas called "Clavicle Antennas" to control their GN Particles, and 00 was no exception, but it adopted a miniaturized version installed in the forehead as a pair of yellow antennas. Previously, the clavicle antennas were mounted on a Gundam's torso, but their position was changed in the 00 to avoid functional interference with the movements of the mobile suit's GN Drives. Additionally, 00 had an extra pair of chest-mounted antennas to support the functions of the forehead's clavicle antennas. As with the other Gundams, GN Condensers were installed throughout the 00's body to store excess GN Particles generated by its GN Drives, enabling the mobile suit to consume a large amount of particles instantaneously when required. However, the 00 utilized newly designed, high performance GN Condensers as the amount of particles generated by the Twin Drive System is of a different magnitude. Like previous GN Condensers, these new GN Condensers could also display various information and data, such as the amount of particles stored. The GN Particles are transmitted to various parts of a Gundam's body using special GN Cables, and while these cables were exposed in earlier Gundams, they have been internalized in the 00.

While the 00 was developed as a general-purpose machine, its armaments emphasized melee combat, like its predecessor, the Exia. Its main armament, a pair of GN Sword IIs, were developed from Exia's GN Sword. The GN Sword II has three different modes: Sword, Beam Saber, and Rifle, allowing the 00 to fight flexibly without switching weapons. The other armaments are a pair of GN Beam Sabers that doubled as GN Beam Daggers, and a pair of GN Shields that could combine into a large shield and are also usable as striking weapons. An enhancement plan called the GN-0000/7S 00 Gundam Seven Sword would equip the 00 with seven blades, and this is an evolved version of the "Seven Swords" used by Exia. Other variants of the 00 are the GN-0000+GNR-010/XN 00 XN Raiser, where the mobile suit combines with an enhanced form of the 0 Raiser, and the GN-0000/XN XN 00 Gundam, where the 0 Raiser's enhancement parts are fitted onto the 00 itself. The 00 was heavily damaged during the final battle with the Innovators and lost both GN Drives. It was eventually repaired, with a pair of improved large GN Condensers mounted in place of the GN Drives. The repaired 00 retained the Twin Drive System and could even use the Trans-Am System for an extremely short period of time.