It is wraithbone primer, then airbrush averland and then a final airbrush of yriel yellow.
Since there's no airpaint for yriel, I premix some with tamiya acrylic thinner. I keep an old Yriel Yellow pot that I fill from other pots and the thinner to have some on hand instead of mixing into a cup every time.
I have some infiltrators that are almost done that I'll post later. I warmed it up some using skeleton horde for the recess shade, which makes it a nice golden color, but you could use any yellow, brown or sepia wash I would think. I prefer the sepia tone of skeleton horde to using the more brown agrax.
I did find that doing averland in between the wraithbone and the yriel was important, it came up to a crisp yellow much faster with the stronger yellow underneath. Yriel doesn't cover the best, but it definitely does better with an actual yellow underneath. From experimentation, I found that just wraithbone -> yriel caused it to get too much of an orange tone, having that averland sunset layer in between kept it towards yellow.
I do between 2 and 3 full coats with yriel and the airbrush. About at two it comes to where I like it.
Edited by WrathOfTheLion, 29 January 2021 - 10:26 PM.