Stop the Mutant Invasion!A bio-engineered virus, created by the super villain mad scientist (duh), turns everyone it touches into monstrous mutants. Most of the country has been mutated, and its up to you to protect whoever's left! Kill all the mutants, they can't be saved anymore.
Just make sure they don't touch you. And If the mutants touch any of the people you're protecting, they turn into mutants themselves and will turn on you. If you lose too many of them, what's the point in going on?