So, I'm not sure if people have seen the other gameplay videos that haven't been shown here, but I've noticed some pretty neat things. They're all pretty short and stuff.
It looks like using RE to block attacks will harm your guard a lot more than regular guarding. As seen in the first trailer, you see a more "active"-looking guard where they almost parry the attack, but their weapon glows more and more with each consecutive attack. In the second trailer, you see...