The world is in chaos. No matter where you go, nothing is there, save the Changed, and buildings in ash, and on fire, creating a pillar or smoke at every city, or what used to be cities. Almost everyone is dead, yet their bodies are nowhere to be found, and there are no hints as to where they could be. This is all they know, and even this they don't actually know yet. They have no recollection of their life before they woke up, all they know is what's going on right now. Their goal is to survive, and find out what happened to the rest of civilization.
The Changed: The Changed are what used to be the various organisms that occupied the world. It's almost impossible to tell what they -were- because all of their features and traits have been super-enhanced, and they are vicious to anything other than the Changed. Each Changed is different, based on what organism it was, and thus, the traits that had been enhanced are different for each Changed. (I'll be making a beastiary most likely so that we don't all have to keep track of them in our heads, and it'll just be easier that way, but if it's not something that is going to be recurring, I'll more than likely not put it in the beastiary)
The world (More in depth about how it works): Not all of the major cities are in ruins, just most of them, and even those that aren't in complete ruins are still fairly decimated, with little resources left available in terms of food and other necessities. The resources that are still left in the cities include most of the manufactured goods, although depending on the item, there may or may not be any of the item. The smaller towns and suburbs however, are slightly more intact, some even looking eerie, but not as if the world is in ruins. This being said, there are, as such, more resources such as food and clothing in these areas.
Other people: There are no other people on the face of the earth. Period. They are all gone, and there is no evidence that there were ever actually any people to begin with.