covets the Earth. He's trying to digitize the lot of us, see, only his exobyte technology has some... unforeseen side effects. At the risk of going all science whiz on you, I'll just say that these nanite exobyte gizmos transformed hundreds of humans into uber-powerful ubermensch. Mutants or even metahumans, if you'd prefer. We're superheroes, really, when you get right down to it.
It's a good thing, too, because Earth's real superheroes couldn't stop Brainiac. Superman, Batman, the Justice League, all of them failed. Even supervillains attempted to save mankind, for a time at least. Before long, though, they did what villains do: They leveraged chaos and exploited disorder for their own selfish ends.
So, yep, it's pretty much business as usual but for the meglomaniacal space invader bent on destroying both sides. Me, I'm just a soldier in this new war, one of a fortunate few gifted with the power of Brainiac's buggy exobytes. Before all this I was a nobody. A minor game critic or some such silliness. Now, my friends just call me the kid. You can call me Kid Critical.