~A personal thing, I always imagined Fenrir to be black with either amber or green eyes.
~he seems a bit too...I dunno, 'fluffly' to me. Certainly not like a cuddly-type fluffy, but more like "I just took a bath and now my fur is soft and clean"-type fluffy. Fenrir was chained up deep in the earth for quite some time before ragnarok, so I'd expect his fur to be a bit more dirty, matted, and wet.
Oooh, great job. I love the way you did the chains, the way they're broken off like that. It kind of implies kind of a slow motion type thing...which goes well with the subject and the rest of the composition. I also like the way the eclipse looks. Nice nice.