Wow, nice!
It's really hard to critique already amazing work. I guess all I have to say is a setting, an environment to put the dragon in would really assist in casting a more dangerous mood. I like what you have going there with the brown yellow tones in the sky. Give that dragon something to perch on with that sky, something to put the viewer in as though they were watching the dragon in real life, and I would be even more floored. I love the level of detail in the dragon's scales. Really amazing. I'm taking a look at your other stuff.