I often describe Invincible like this
"Imagine you were around when Spiderman first appeared (most of the people I am around were not around then, myself included) and you new this character was something special." Even though superheroes have been done to death, this book brings new stuff. It's really great. And somehow it is able to be SUPER violent and somehow not seem gratuitous. I think Allen the Alien, is one of the few true hero souls in the book (unless something happened that I don't know about). enjoy.