I know for absolute certainty that Volkan Baga works in oils.
Pretty sure Chris Rahn does too.
That mother of runes has some very strong influences from Gustav Klimt, which is very interesting.
I'm really surprised to hear that about Baga! I've just been assumed he worked digitally because there's such a... well I'm not sure how to describe it, exactly, there's a quality to the color layering that I associate more with digital painting than traditional media. To get the kind of lighting and gradation of color he gets with actual paint... man, that's just unreal.
Granted I say that as someone who vastly prefers the handling of digital paint haha