Here's the most basic synopsis of the general idea-
(This is Kurai's sum up of it.)
So, now we have a pretty general feel for the Roleplay: the setting is a post-apocalyptic desert world plagued by acid rain. The characters take the role of a Hunter (a specialist in taking down threatening monsters) that belongs to one of two tribes, either the Humans or the Hybrids (I think we should come up with actual tribe names, but more on that later). Their goal is to attain two legendary artifacts that will open the door to an unexplored cave region, said to hold the key to stopping the acid rain and also great treasure (threw that in because I figured legends get aggrandized over time, though we could add treasure as well). When they finally open the door, they discover a vast cavern network that ends with the Acid Monster. Slaying that will cause the acid rain to cease and will allow the world to rebuild again.