A Force of No Equal

Three waves decimated the earth. In the First Wave: Snow Day, they came with the snow to destroy as many of us as possible. During the Second Wave: A Trip to the Zoo, they took over our government, our armies and our own bodies. And finally, in the Final Wave: A Hike in the Mountains, one of the last members of the human race tries to run for a place to hide and wait out the invasion, only to find that there is literally no place on earth left to run.

In order to get our planet, they had to get rid of us.