Then, why should the NWC ever think of using it?
Either Kunous should have this tech (barely plausible, but it's Ranma 1/2, on the other hand) or you need to have a high ass-pull skill to pull this off.
Honestly, is there some reason you feel the need to throw this stuff out impulsively like this? Because I'm not buying you could have thought of the ramifications of that position for even two seconds. He asked for Post Apocalypse setting, not ye olde contrived Zombie film.
Post-apocalyptic world is a world where 99.9% of the zombies ran out of steam and decayed to dust (just how high a success rate would the random mutations have? Think of the ghouls from Fallout and their numbers in relation to the pre-war population). So, while the Apocalypse itself is a cliche zombie story, it all happens off-screen. When Ranma enters the picture again, the world is balanced. Empty, with small populations of humans and mutants.
Ah. It can be funny. Imagine Ryouga succumbing to the virus, to achieve a monstrous form and inhuman longevity (cue the Fallout ghouls again). And then Ranma encounters him. Ryouga the Super Mutant... hmm...
P.S. Well, he have said "Fallout", hadn't he?
