I asked mantic this question a few months ago
And it turns out Nathaniel at mantic is awesome
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Hi Nate,
I have spoken to Dave the Painter our Blogger and such! Here is an in depth version on how to get the colours exactly right, these are straight from the person who painted them:
White undercoat
Basecoat of Rakarth Flesh mixed with a touch of Coat d'Arms Dark Earth
Army Painter Strongtone in the recesses
Fade shadows in with Charadon Granite
Highlight with neat Rakarth Flesh
Highlight with Space Wolf Grey/ Blue Horror / Coat d'Arms Lupine Grey (any will do)
Black is undercoated black
Highlight Ad Mech Grey
Second highlight Fortress Grey
Final highlight with Space Wolf Grey/ Blue Horror / Coat d'Arms Lupine Grey (any will do)
He also gave me a much simpler version that wont be exactly the same or as detailed but be much easier to do, the simpler version is:
Games Workshop paints:
Baneblade Brown
Wash with Nuln Oil
Reapply Baneblade Brown
Highlight with Karak Stone
Using Army Painter:
Monster Brown
Wash with Dark Tone
Reapply Monster Brown
Mix Ash Grey and Monster Brown and highlight with that.
I hope this helps, It was a nightmare getting all this right from him, there's so much detail!
Kind regards,
Nathaniel
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I went with a rakarth felsh, null oil wash, more rakarth flesh then bleached bone In The end