Re: Supers world building...
In reply to spectre (msg # 1):
Martian's wild card series used an alien made gene that respond to stimuli internal and external to mutate folks. If born special, you're s mutant, if a hazardous environment triggered something, you are altered, etc.
Just set the date of the virus carrying the gene back a few 10s of thousands of years and you explain secret offshoot races, pulp heroes, newer mutants, super smart techs and engineers, even folks altered in a lab by someone who may know how to recognize the X gene (which could be anyone that knows how to run a DNA test) and knows, more or less, how to stimulate it to achieve a desired result. "More or less" covers the folks that only.think they know, as well as those that actually might.
Set it back about 250 thousand years, and you could explain humanity.