[analytic_kernel]

AFAIK, you can't control the rarity of particular hero events. In one of the "heroes" threads that I read, someone suggested that there seemed to be a preference for certain kinds of heroes given certain scales. But, I never saw any statistically-significant evidence or anyone's analysis of Dominions code to support this or any other kind of preference or weighting.

I think maybe Illuminated just meant that one should create "superhumans" sparingly in mods.