Before there are five Gundams, there is only one - and it exists strictly on paper. It is AC 180 - 15 years before they send their own respective custom-built Gundams to wage guerilla warfare on Earth - and the five eccentric scientists Doctor J, Professor G, Instructor H, Doktor S and Master O, have just completed designing the first mobile suit, the OZ-00MS Tallgeese. Seeing their work being put to oppressive use in the form of mass-produced OZ-06MS Leo - and spawned by the assassination of space colony political leader Heero Yuy - the five scientists decide to design their own mobile suit which can overpower OZ's forces. This mobile suit is the XXXG-00W0 Wing Gundam Zero, and it's a design to truly be feared. In addition to being extremely maneuverable, it sports Gatling-like machine cannons, beam sabers, and an extremely powerful twin buster rifle, capable of wiping out entire groups of mobile suits in a single shot.
However, one more factor puts the Wing Zero above everything else: the cockpit's "Zero System," which allows the pilot's mind to interface directly with the Gundam's combat computer. Although the exact nature of the Zero System's operation is unclear, it appears to operate by "sampling" the pilot's thoughts and, combining them with current combat data, presents the pilot with various alternate outcomes. Thus, depending on the pilot's mood, the Zero System can tell them how to achieve total victory... or decisive defeat. Nevertheless, the mental stresses the Zero System places on the pilot are too great for any ordinary human to handle, and even the five mad scientists see the dangerous turn their work is taking. And thus, the Wing Gundam Zero project is shelved. A copy of the plans goes with each of the five scientists when they break up and go underground to pursue their own individual plans for revolution against OZ. The Wing Zero design serves as a base model for the five Gundams that are actually built and sent to Earth.
In AC 195, unfortunate circumstances place XXXG-01SR Gundam Sandrock pilot Quatre Raberba Winner in space without a Gundam, with a dead father, and with enemies of the very space colonists he was fighting to free. Wracked by a serious mental imbalance, Quatre discovers the abandoned work of the five scientists, and he builds the Wing Zero. Mindless of its dangerous Zero System, Quatre takes off to destroy anyone and everyone fighting in space. Though his mental condition is temporary, the Wing Zero's power proves truly terrible, as Quatre uses it to destroy an entire space colony. After that, the Wing Gundam Zero passes from one pilot to another until it lands in the hands of former OZ pilot Zechs Merquise, and then Gundam pilot Heero Yuy - two of the only humans known to actually master the Zero System by making use of its advantages while preventing it from driving them mad. The Wing Zero remains personal mobile suit throughout the Eve Wars and is destroyed in AC 196 while attacking the Mariemaia Army's seized headquarters in Belgium.
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