Wow. This is awesome, in the true meaning of the word: awe inspiring, humbling. Really great work. I love the pictures of the monster throwing different fireballs and disks and lightning. I really sense the movement!
I have to say that the existence of all this art greatly enhances the credibility of this game, or the level of respect I feel it deserves. It may even make the difference between me buying it and me not buying it. Of course, I'll have to wait for the reviews to make a final determination, but the importance of concept art for the success of a project like this should not be underestimated.