What Killed the Big Lizards?

The most surprising thing to me is the facts that this whole story of the dinosaurs dying keeps on changing. Some scientists claim that climate changes killed off the dinosaurs. Others say that there was a massive eruption. And of course, there is the rock that fell to Earth and killed off the dinosaurs. Now there is evidence of a cooling period that killed the dinosaurs. The heat didn't kill the beasts, it was the cool down that killed off the beasts. I find that very unusual because that big impact didn't kill the beasts, that big impact caused the earth to shut down and go blank causing the temps to cool. This was what really killed off those beasts. The meteor impact was the first stage in the extinction of the dinosaurs, but the cool down really did away with the dinosaurs. I could believe this thought. The only question I have is what happens to is? What will wipe us away?