Technology & Combat Characteristics
Developed by the UN Forces, the GN-XII is the successor of the GN-X. In the GN-X series, older models can be upgraded into newer models by switching out parts, and this meant that some of the GN-XII units are retrofitted GN-X units. The GN-XII also incorporated data from the GNX-604T Advanced GN-X, and has hardpoints on its shoulders and waists for mounting weapons. Another feature of the GN-XII is that the GN Particle Generators on its chest and waist, which are for controlling GN Particles, have been miniaturized compared to those of the GN-X. The GN-XII is later upgraded into the GNX-609T GN-XIII, which retains the hardpoints system.
History
A.D. 2309, a UN Forces missile base in Africa was assaulted by an anti-UN group, whose members include the rogue Gundam Meister Fon Spaak, with the intention of taking over the base so that they could negotiate with the UN Forces.
The anti-UN group split into two teams, one team lured away the AEU-09 AEU Enacts and SVMS-01 Union Flags guarding the base, while the other infiltrated the base. This second team was caught off guard when one of their mobile suits was taken out by a long-range beam attack, and it was revealed that the base's guard machines also included a GN-XII, a GNX-607T/AC GN-XII Sword and a GNX-607T/BW GN-XII Cannon. Intelligence obtained by the anti-UN group had earlier indicated that the base did not have any GN Drive Tau-equipped mobile suits due to its low importance, among other reasons. Fon and his GNY-001F2 Gundam Astraea Type F2 then battled against the three units.
As the GN-XII, GN-XII Sword and GN-XII Cannon attack in perfect unity – the GN-XII and GN-XII Cannon shooting from close and long range respectively, while the GN-XII Sword restricted the Astraea Type F2's movement through close combat – Fon had a hard time fighting them off. With the three GN Drive Tau-equipped mobile suits occupied by Fon and his Astraea Type F2, the other members of the second team rushed towards the base. The GN-XII then left the battle with Astraea Type F2 to stop them, and end up fighting a SVMS-01SG Union Flag Ground Package Shell Type.
When the pilot of the Union Flag Ground Package Shell Type was informed by his companion who had entered the base that this was all a trap, that there was no missiles, only old rockets left behind from the construction of the Orbital Elevator, he lost the will to fight. The GN-XII closed in to deal the final blow, but was destroyed by a GN-XII Sword's GN Buster Sword thrown by Fon's Astraea Type F2. The anti-UN group eventually won the battle. Fon had anticipated the trap, and was after the base's old rockets all along, which he then used to blast off into space with his Gundam.
Months later, around AD 2311. Fon and his Astraea Type F2 attacked a manufacturing facility in space belonging to the UN Forces to acquire resources for his new plan. The facility launched all its GN-XII units to stop Fon, but they were all defeated.