(the quarantine zone makes up most of texas and Louisiana, the land of the quarantine zone stem from first several big labs, experimenting on ancient and new, fabricated diseases, but, after the fall of biological nukes, nukes that do less explosive damage, and more mutating radiation, causing a bit of destruction, and more mutations throughout most animals, sure theres a few un mutated animal populations in less overly radiated areas, but most are mutated atleast slightly, the diseases in the labs broek out from the shockwaves of the three bio-nukes, fighting over the bodies of dead and alive scientists stuck inside the labs. two infections prevail. one, the corbeva virus, a virus that infects humans and a few mammalian animals, such as deer and boar, turning them into mindless creatures, more primal, using primal weapons like bricks, rocks, and other things, the infection turning their bodies more fragile but are alot more resilient even if they have their chest ripped open, sort of like zombies but will die if they arent treated by other pack members, yes pack members, they are turned into animals, and are smart enough to be able to patch up their brothermen with certain mutated plants, like adhesive sterilizing leaved plants called bandage ferns, used as primitive bandages. but after a while the infection worsens they grow fangs, and if logn enough will become more bipedal, their spine becoming stronger and breaking through their back. turning them into spider zombies that spread the infection, and then theres the cordiseps. a fungus like infection that evolves and grows, living in the most mutated areas, it works as a hive mind and learns, evolving the next units it makes to combat any enemies, mammals like dears, mutated into big antlered robust creatures, being docile still but alot more defensive when in herds. with boars becoming more carnivorious and have big hook tusks, cows, rams, and goats have mutated to be bigger, and have bigger horns. insects and arachnids grow bigger aswell, and reptiles like gators, lizards, and snakes, grow bigger, three species of snakes evolving, one called the Gigaboon viper, a strain of Gaboon viper species that grew large, faster, and grow rock like growths on their back to help disguise themselves in the desert, ambushing their prey with a venomous bite to any part of the body, the venom killing muscle tissue if not treated, being about 15 feet long, then theres the species of copper head, the brass head, a fast, chase down species of snake that will chase prey down until one gets tired, delivering a venomous bite to the neck or back, killing quick, growing to 13-16 feet. and finally the evolved version of a cotton mouth, a rag mouth, having grown to larger sizes, swimming in the supportive liquid of water, causes them to be the biggest snake of the zone, having darker, dirtier coloring to their mouth, giving them their name, they are atleast 18 feet on females, who are smaller then males. they compete with the mutated species of gator, called the shatter jaw, growing to the size of a deinosuchus, they have wider heads, and bigger teeth, with two pairs of giant teeth that stick out, used to crush and hold prey, feeding off of giant mutated moose, called a shredmoose, they are dumber, but bigger, giving more meat, and are the preffered prey of shatter jaws, they grow thick coats in the cold winters, and sparser coats in the summer. the zone is very abandoned, having only a few well known settlements, people fighting over something as simple as a car, a weapon, food or water, which is a lot more common than normal apocalypses depicted in media, but arent super common, being between uncommon and rare at best. there are raiders, the irradiated scum that infests the zone, zoners, faction from the goverment meant to keep stuff secure and to help civillians, wanderers, nomads that contain most of the survivors in the zone, settlers, people that settle in places alot more than wanderers, be a mutant, be a monster, be a human, and start your story in the zone)