A variant of RX-78 series, the RX-78XX Gundam Pixy was a high performance close-combat ground mobile suit created by the Earth Federation Forces for use by their ace pilots during Operation Odessa. The Gundam Pixy was significantly lighter than its RX-78 brethren, due to removing the core block system and thrusters for outer space, and as a consequence is faster and more agile. It also possessed enhanced apogee motors which allowed it to achieve burst thrust exceeding that of the RX-78-2 Gundam. However, it is relatively lightly armed, with head-mounted vulcan guns, a shell-firing submachine gun and a pair of beam daggers.
he RX-78XX Gundam Pixy was developed under the "G-4 Project", a next-generation MS development project jointly conducted by the Federation Space Force, Army, Navy, and Air Force near the end of the One Year War. Three Gundam Pixy units were known to have been constructed, with Unit 1 being sent to Belfast, Unit 3 assigned to Africa, and Unit 2 being stored at the Albatross Base in the Gobi Desert in preparation to be transferred to the Pegasus-class assault carrier White Base for use at Odessa.
When Principality of Zeon forces commenced Operation Desert Dragon and attacked Albatross Base. The Gundam Pixy was commandeered by Captain Bork Cry of the Albatross transportation team to fight off the Zeon mobile suits. The ultimate fate of the Gundam Pixy is uncertain. The unit may have been destroyed on the night of October 19, U.C. 0079, engaged in a fierce battle against Captain Henry Boone, leader of Zeon's Wolf Gar Team, piloting his MS-08TX Efreet, and the rest of the Wolf Gar Team, which had successfully infiltrated Albatross Base. Major Nacht Gaddish, commander of the Albatross Base, fled in a Medea, abandoning Bork and the Gundam Pixy. In the end only one thing is certain: the Gundam Pixy never arrived on the White Base as planned.