The Xatu wings look a little too copy-and-paste ish with those black lines attaching it to the body, and the body has poor shading (there should be darker shading underneath the neck, not lighter). The eyes look like the orbs from a Sceptile's back, and the horns aren't quite blended well with the head. The outline's a bit too black, and needs some lighting effect from a certain direction >.O It's not the worst I've seen, but it's not the best; I suggest looking to see how a bird Pokemon's belly/body is shaded, and study the transitional pixels that blend with the black and other colors for the outline D: