I've grown tired living on my old world and began to move out - living into another world, a different dimension. What greeted me is an entirely new world called Earth. But moving here gave a detrimental effect, a catastrophe.  A huge natural destructive force swept the entire Earth - destroying most living things and disarranged the lands. Only hundred million humans survived.   A few years after, people from my old world began to appear into this world. Some were crippled, some were not.   I need to find out and help them...