Sandrock-Kai: After the self-destruction of the oringial Sandrock, it's Gundanium shell was taken by the Maganacs and re-built. Later, it was given furthur upgrades by Howard aboard the ship peacemillion. The renovations did little cosmeticly, but Sandrock was now able to fight efficently in space.
Wing Zero: He didn't just pilot this Gundam, Quatre built it. Stranded in space without a mobile suit of any kind, Quatre stumbled upon the uncompleted works of the five scientists, and finished the job himself. The result? A Gundam that used the insanity-causing Zero System, which pushed Quatre off the edge and caused him to even destroy an entire colony.
Story: Before Gundam Wing: On the colony L-4, a problem arose in the human birth process. Not all humans were no longer born naturally, and were instead grown as test-tube babies.
More coming soon! "Come on, Sandrock... it's way too early to be defeated yet!" - Quatre Raberba Winner "Heero, it's human beings who fight against each other. But those humans are now depending on machines to gain their strength to fight. Heero, it's mistaken. This Gundam is a MISTAKE." - Quatre Raberba Winner