I don't see too many changes.
The whole icon could use more definition.
Atm, the icon looks too unclear and flat, is kinda confusing, nothing is precise here.
That detail, above his teeth, looks like it's deeply carved in his upper jaw or like that part(unnaturally very close to his eye) was removed from his jaw, mainly coz of wrong shading.
The head needs to have a well defined/correct shape from the angle that u chose.
For example, the eyes, the horns, the snout, etc. aren't well positioned from the angle that u chose to draw his head.
All the details are drawn using thick lines, this giving the impression of unrefined, unfinished work.
It's all about perspective, proportions and shading.
I advise u to take a look at some artworks(pics and 3D models) that represent dragons, to observe how a dragon head could be, the position/proportions of his head's main features(eyes, jaws, horns...)
It'd be nice to see at least some improvements regarding definition and shading.
Also, a more accurate work will be much appreciated.
Approved
