When the XXXG-01S Shenlong Gundam was captured and destroyed by OZ's forces in AC 195, the extremely durable gundanium-made remains of that mobile suit were taken to OZ's lunar base and mobile suit factory for storage. The five scientists who had built the Gundams plaguing OZ were also at the lunar base, captured and forced to develop new mobile suit technology to secure OZ's rule over Earth and the space colonies. Despite their apparent "cooperation," however, the scientists also began rebuilding both the Shenlong and the XXXG-01D Gundam Deathscythe in secret, preparing for the day when captured Gundam pilots Chang Wufei and Duo Maxwell could return to the battlefield. That opportunity came when the Romefeller Foundation - the political force behind OZ - became split over a number of issues, and the "Treize Faction" of OZ attacked the lunar base, which at the time was still under the control of Romefeller loyalists. During the chaos Lady Une released both Duo and Wufei with their partially upgraded XXXG-01D2 Gundam Deathscythe Hell and XXXG-01S2 Altron Gundam.
The improvements given to the Altron were dramatic. The old beam glaive was replaced with a double-ended twin beam trident, and both arms were outfitted with Shenlong's highly effective "dragon fang" extending arms and claws (hence the Altron name, taken from the Chinese "ertou long" or "two-headed dragon"). Along with increased mobility from it's "wing binders" on its back which enhances it's mobility in space, the Altron also mounted a pair of beam cannons on a "stinger tail," giving it effective ranged firepower for space combat (both the wings and tail stinger were removed in the OVA version) The new Altron was henceforth a menace to the White Fang army during the "Eve Wars".
After AC 195, Wufei, wanting to see what the true meaning of justice is, took the Altron with him to the newly formed Marimeia Army instead of sending it into the Sun with the other Gundams. Wufei fought against Heero Yuy twice, once when the latter was piloting an outdated OZ-06MS Leo and the second time when Heero piloted a revived XXXG-00W0 Wing Gundam Zero. Wufei, seeing that true peace could not be achieved through Operation Meteor, rebelled against the Marimeia Army during the battle in Brussels. After the rebellion, the Altron was later self-detonated by Wufei