Concentrating on further refining the available details, add some ambient shadow to the base of the ice shards. As they are semi-translucent, the base should be the darkest and they should lighten as they taper off into a point towards the top as they are thinner and allow more light to pass through them. At this stage, we can also start adding some analogous colours, mostly a turquoise blue to the tips of the ice (Fig.06). Don't go overboard with color usage, just hint at it to test out if it will work. We can increase the saturation later on if it feels right.
Start to define the form of the head a little more, especially the upper beak as this will be a major point of focus. The tongue feels a little stiff and lifeless to me so I'm going to introduce a little bit more rhythm to it. After all, this is a wild animal and I want all aspects of the creature to emphasize this fact. Towards the top of the griffin's neck, taper it off and increase contrast by adding darker tones to the image.
You may find there are a few harsh areas of areas that could do with being toned down. We want to make sure the viewer's eyes is not distracted by too many points of interest or contrast - particularly the inner membranes, which have a harsh, thick, white light. This might be something I eventually work back in, but for the moment let's paint it out as it's messing with my evaluation of the overall work.
Working on the form of the neck, treat it as more of cylindrical object and darken the underside, as it would receive less illumination with the lighting setup that I have chosen to go with (Fig.07).
At this point, I've decided that I will be relating my tonal rendering to two major light sources - the harsh rim light from the left of the image (the sun) and a slightly less harsh fill light from the front, which will act to illuminate the forward facing details of the griffin. On the ice cliffs in the background continue to add darker tones and on the tips begin to simultaneously add more lighter saturated turquoise. You can see how quickly the ice takes shape just by laying in the correct values in the right place.
Creating a new layer set to Color, lay in some darker pinks for the ear canal, tongue and membrane area (Fig.08).
Notice that I haven't completely covered the blue undertones; this is because I am trying to preserve that blue throughout the image as a unifying tone that will tie disparate colors together.
Next, add some darker oranges and some yellow to the beak, again using the same layer set on Color blend mode.
Wanting to give a feel that the beak is semi-translucent (similar to the ice) let's add some lighter yellow tones to the external thinner parts of the beak. The effect is over-exaggerated for the moment, but it gives nice dimension to the feature. We can tone it down later on (Fig.09).