More Than Human

This isn't your any other "zodiac meets aliens" story (not that I've read many).
Instead of them being powerless and trying to sneak into their enemy base, intimidated by such powerful forces, that's not the case here.
In this story, the zodiacs are a feat not to be challenged.

-------------------------------
It's the year 2221.
A group of twelve teenagers attends a prestigious academy. So prestigious, that only 1% of the population (being 8 billion) can be accepted. What the academy does though, is not for everyone.
They train with extraterrestrial-powered weapons, as well as among other things. And that can be extremely dangerous.
But this group of twelve teenagers is known as one of the most skilled people that have ever existed.

So...what happens when a civilization of an unknown species from another world threatens to dominate the entire human population?
Well, one thing's for sure:
The zodiacs aren't gonna let themselves be taken that easily.