I know this isn't much, but with the limited background I've been given, this is all I got right now. I'll probably come back later and add on when I've got a few more ideas.
Well, I started working on it recently so there is not that much to it yet. Here's how it's going so far:
My idea was that the reason Pokemon are even in slavery to humans is that Pokemon are put under some kind of mind control when captured, inflected by pokeballs and/or badges. Mewtwo is able to break the mind control because of his strong psychic powers. He goes around freeing Pokemon and many of them join his side, because most Pokemon are not willing to fight for humans anymore when freed.
Human's have guns, so Mewtwo forces at first end up mostly composed of Pokemon that can handle bullets, such as armored pokemon like rock and ground types, and Pokemon able to evade bullets such as flying types and ones fast enough to dodge bullets.
At frist they wipe the floor with the humans, because Mewtwo keeps breaking the mind control of their Pokemon, so the humans end up with only guns to defend themselves, and like I said Mewtwos forces are strong against guns.
But it turns out that Team Rocket has some sort of stronger mind control that Mewtwo can't break(at least at first), so Team Rocket ends up being the only humans that can use Pokemon, and they use ones strong against Mewtwo forces, so Mewtwo begins to lose. Team Rocket takes over the human side and it basically becomes Mewtwo vs Team Rocket.
In desperation, Mewtwo, going by a old legend, manage to summon either lugia or Kyogre. (They're gods in this story.)
lugia (or Kyogre) get enraged and decide to remake the world, which mean destroying it first. [spoil] lugia or Kyogre puts an entire continent under water, killing billions. Mewtwo has a epic battle with lugia (or Kyogre), and wins..[/spoil]
At this point I'm not sure what happens. I was thinking maybe [spoil] Mewtwo gets betrayed because one of his associates gets freaked out over the destruction lugia (or Kyogre) caused and they decide things have gone too far.[/spoil]
It ends [spoil] bittersweetly. Mewtwo wins, but billions have died and their is still little pockets of Pokemon in slavey. Also I might kill Mewtwo off. Not sure.[/spoil]
That's what I got so far. I figured I would add more before the end, because right now it ends too abruptly. I would like to work more legendary battles in, but I'm not sure how to do that yet.
I assume this is to be on the long side, yes? At least several chapters? .
I don't know. I've noticed I tend to write laconical even though I don't really intended to.