In the year 2230, 5 years before a test reactor that destroyed humanity went off, a pair of wealthy scientists both husband and wife believed the reactor would never work and tried to persuade the World Government to cancel the test but were denied due to lack of hard evidence. The pair of scientists predicting the end of the world hastily returned to their lab and poured all of their resources into their field of work creating an experimental drug that could initiate an evolved state of human DNA that would increase a human's biological adaption in hopes of negating radiation poisoning .
At the time they only had enough for a single dose and so made a decision. Using the highest technology of the their era which was labelled """"Black technology"""" which was banned to regular civilians and only allowed for military use , they wiped their only son's memories and instead implanted memories of the greatest martial artists and styles of combat that Earth had ever recorded in hopes he would be able to survive the new world that would be created by the exposure of radiation, placed him in a cryogenic stasis craft and sent him out of the Earth's orbit.
However, the test reactor went above their expectations and completely and thoroughly destroyed Earth. The cryogenic stasis craft had been blown into a wormhole and after a few hundred years, it's autopilot had been finally once more been engaged.