Berg's past is a complete mystery. All that is known is that he seems to have been a mobile suit designer for a long time. However, the accelerate rifle that he designed for the G-UNIT was said to have been originally developed by OZ's quantum physics lab, hinting that he was a former OZ scientist.
In A.C. 185, Berg sought to use the resource colony MO-V for his own plans. However, he was opposed by Mark Bernett, a designer of spacecraft engines. Because of this, Berg orchestrated a shuttle accident, killing Mark and his wife.
Having removed the one obstacle in his way, Berg was hired by Roga Hermann to become head of MO-V's development office. Using MO-V's resources, Berg developed the OZX-GU01A Gundam Geminass 01 and the OZX-GU02A Gundam Geminass 02, two mobile suits that were collectively known as the "G-UNIT". Ironically, they were piloted by Odin Bernett and Odel Bernett, the orphaned sons of Mark Bernett.
In A.C. 195, MO-V decided to join OZ because of Lady Une's propaganda. Meanwhile, the development of the G-UNIT was kept secret, and Hermann hoped to present them to OZ once they are complete. However, Berg secretly leaked intelligence about the G-UNIT to OZ Prize, an independent unit within OZ answering only to the Romefeller Foundation, causing them to attack MO-V.
During a battle between the G-UNIT and the Stardust Knights, the leaders of OZ Prize, Odel was apparently killed when his Geminass 02 was sent into a space minefield. However, Berg saved him, gave him a new identity as "Silver Crown", and ordered him to infiltrate OZ Prize. He then transmitted modification schematics for the Geminass 02 to OZ Prize, allowing them to modify it into the OZ-10VMSX Gundam Aesculapius.
In order to draw out the full potential of Geminass 01, Berg demanded Lucille Aisley to have Odin train harder in activating the PX System, saying that his G-Unit is perfect and it was the pilot's fault that it lost to modified Leo. He then sent a transmission to the Stardust Knights, asking them to come pick him up. In the ensuing battle, while Odin fought the Aesculapius piloted by Roche Nattono, the other two members of the Stardust Knights, Kratz Silvy and Broom Brooks, led an attack on MO-V itself in order to extract Berg.
Meanwhile, Lucille finds Berg putting on an astro suit in his room. Berg asks her to send his regards to Roga right before Brooks breaks his window with the OZ-06MS-SN3 Leo-N and catches him (nearly sending Lucille flying into space in the process). With their goal accomplished, the Stardust Knights broke off the fight and retreated.
Back at the OZ Prize flagship, the Grand Chario, Roche was angry at the fact that he was unable to defeat Odin and the Geminass. At this point, Berg introduces Silver Crown to the Stardust Knights, and says that he will be piloting the Aesculapius from now on. Roche seemingly recognizes Silver Crown's true identity.
At MO-V, Roga was furious that Berg was a spy all along. However, communications officer Tricia Farrell noted that Berg left behind data for the G-Unit's new parts, as if he wanted them to continue the development of the G-Unit. Meanwhile, Berg sends Silver Crown in the Aesculapius to attack MO-V. Silver Crown proved to be much better at piloting the Aesculapius than Roche, and when the Geminass activated the PX System, he activated the Aesculapius' PX System as well, much to the shock of Odin, since he and Odel were the only ones who can use the system. However, the battle was interrupted by Roche in the OZ-06MS-SS1 Leo-S, who told Silver Crown that he was the only one allowed to defeat Odin.
At the Grand Chario, the Stardust Knights were confused that the Romefeller Foundation was not responding to their communications. Unbeknownst to them, Berg sabotaged their communications, disappointed that OZ Prize was nothing more than a rich boys club, and that the Foundation has made a little girl as their new leader. He tells Silver Crown that they must prepare for the next stage as a shadowy figure approaches in a shuttle.
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