"Darwin's World is a role-playing game set in the wild, inhospitable world of mankind's ruin, after a series of devastating wars that brought the human race to the brink of extinction. In a world where radiation has altered the very course of nature, mankind has ceased to exist in its current form. Mutations and genetic variations are the edge separating a species from life and death."
The worlds a bit like madmax, or if you've played it - interplays "FALLOUT" game series on pc.
Do a search on Wiki for fallout 1 or 2 and you'll get a clearer picture...