King and Torment

Tribal gangs in a cyberpunk future of the year 2042.
In a world dominated by mega corporation sects, those who struggle for the freedom of choice must band together and adopt a "barbaric" lifestyle in order to survive. Disease, famine, and chemical waste are plentiful due to the corporate sects keeping their resources barricaded in their floating ecosystems (though of course not the waste).
This led to animals and plants rapidly mutating and adapting; looking like an abuse of natural selection. The people of the sects were horrified and disgusted with nature, but where they found filth, the gangs found animal comrades. The gangs saw the strength in these new beasts, but also had to acknowledge their new weaknesses. Through mechanics and engineering, the best minds of the free people created an endless variety of new appendages and prosthesis for their animals, from the basics of a flight cage for farming catfish-ram to full fledged war mounts ready to take on cities and fortresses.