Along with Ragnar and Ulrik the Slayer I have painted Njal Stormcaller, the most powerful Space Wolf Rune Priest. Pictures, as usual, are below.
Looking at the codex, he is a very powerful model, with a focus on interesting ways to destroy your enemy at range. His Jaws of the World Wolf is a nice way to get rid of low initiative tough models, and his Murderous Hurricane (I think? The spell that does hits and the target takes dangerous terrain tests if they move) looks like a good way to make sure that his target can only make bad decisions. If placed with a couple of Long Fang units he can make your long range fulcrum very effective while mounted Grey Hunters and Blood Claws act as the offensive lever arm.
The model is painted in the same method to start with as Ragnar: a dark grey to very light grey undercoat. With Njal I wanted to do a bit of source lighting however (Victoria Lamb is fantastic at this) so right from the start I thought about where I wanted the light to come from and highlighted accordingly. I decided that the staff would cast off a bright, firey light and that it would come from the whole staff. The miniature was then painted in much the same way as Ragnar, but again with an eye on where the light was coming from.
When it came to painting the source lighting I made up very dilute dark red, orange and yellow (seperately...) washes and starting with the red painted over the top of all my previous work. The red was fairly widely painted on, with not much finesse. I then moved to the orange and again washed it over the top of the red. This was a much more focussed wash, and was reapplied several times. I then took the yellow and hit the highlights with this. I then worked the lighting until I was happy with the look; if I felt an area needed to be darker I painted some more red on, with some orange maybe worked in while it was still wet. Overall I am happy with the look. Below is a close up of the face, which I am fairly happy with, and best shows off what I am talking about.
The base has been done in the same manner as Ragnar's although there is no static grass and some of the rocks where included in the source lighting attempt.