GTA: Toxic Town
You are a quality assurance for a large toxic company. It is your job to ensure the company that everything work as fine as possible. But, one day, you found out that there was a leak among the barrels and it has change you into something hideous. Soon, the whole town was mutated. You need to get to the safe zone to be able to get to the next level. This game has a timer, so you need to keep going or lose without doing anything at all. You would be fighting some hideously deformed mutants, so you need to shoot them.