Here is his back story:
Nu Gundam ver.4.20 Prototype Psycho Frame MS - Experimental
The project started immediately after the development of the Nu-Gundam in U.C. 93 and was finalized in late U.C. 94. This unit is the 'missing link' between the Nu-Gundam and the Unicorn Gundam. This Nu Gundam was never intended for battlefield use and was instead used to test out different theories on psycho frame technology and the controversial “Psycho Joint” tech which uses the actual genetic material from the pilot to create a more cohesive man/machine unit. While the experiment was a startling success the fact that after the procedure the suit could never be used by another pilot was deemed to inefficient to see itself into final production. Later the design would be finalized in the Unicorn and Banshee models which didn't require direct DNA from the pilots but instead used the principle of syncing brain wave patterns with the psycho frame which produced a more efficient and somewhat less problematic system than that used in the 4.20.
One of the key design features of the 4.20 was the reshaped V-fin to an inline double antennae. This antennae works similar to those of earth insects, “sensing” the ambient energy in the area and relaying it through the modified helmet camera-turned-receiver to the pilot giving an unparalleled amount of environmental data. Psycho frame receiver modules are placed in relatively equal sections around the suit providing the pilot with previously unseen information over all aspects of suit integrity.
The specially designed psycho joints of the 4.20 complete the BASIS System (Battlefield Area and Situational Information Suite), enhancing maneuverability and suit awareness to all new levels. The exact making of the psycho joints is a classified process but it involved treating the Nu-Type pilot's blood with nano-machines and mixing that blood into the special psych frame "paint", which is really more of a nano-machine packed 'gel' that works in conjunction with inner suit technology) The frame’s power had to be adjusted very specifically and meticulously in order not to overload the pilot with too much sensory information. After prolonged tests and exposure to the system the pilot and suit developed a symbiotic relationship. The pilot would experience anxiety and panic attacks if he was away from the suit for too long and the suit itself would not respond to any other pilot.
Through meditative practices the pilot was eventually able to overcome this but the suit remains one that can only be piloted by him. Through extensive training and adequate power supplies, the pilot exceeding all expectations by being able to control the suit through the power of his mind, even outside of the cockpit. After this became apparent all research into this field of psycho frame technology was prohibited, deemed by the executive directing board to be too dangerous for field applications. Upon witnessing this exhibition, the lead scientist and architect of the psycho joint theory and design, famously exclaimed, “What manner of monster have I unleashed upon this world?”
One of the few sorties this mobile suit would have would come 3 years later alongside its predecessor, the Ebon Enforcer Sinanju aka the Anti-Gundam for a top secret mission the details of which are still kept under extremely tight security. Special note - the 4.20 was issued a stock shield and beam rifle of the regular Nu Gundam but the pilot preferred to use the suit with as little weight as possible using a double funnel configuration for proper weight distribution. The pilot felt that the multirole funnels, forearm mounted beam sabre and head vulcans were enough firepower for the mission specs and position required of the suit. Preferring speed and control over power and defence the pilot would often sortie which sections of the suit unarmoured reducing weight and enhancing the effectiveness of the BASIS system. If the pilot had his way he'd sortie in just the frame but the engineers wouldn't have it. As such the suit is often used without the right shoulder and leg armour.
The pilot was notorious for acquiring weapons on the field and adapting them into his own system and fighting technique. The funnels have been upgraded to produce individual I-fields when fully opened in addition to being able to absorb ambient energy while partially opened and expel that energy has force blasts in it’s conventional U configuration. The frame of the 4.20 Nu Gundam is made of an experimental composite material to reduces the overall weight of the suit, increasing maneuverability, agility and speed and thus conversely, power. The leg thrusters has also been upgraded and redesigned for increased range of motion and output. When not participating in top secret missions the pilot works as a hover cab driver on side 7. No one knows about his real job.
