I love this piece, great work. The mix of the painterly clouds with the hard black lines in the foreground give it a really unique feel. Reminds me of European Comic art a little. All that and Giant Killer rules!
Love that composition. One of the things I think is very difficult to achieve in art is a genuine sense of scale when dealing with HUGE imposing robots, monsters, buildings etc. That 'pit of the stomach' feeling. You did it well here.