I wanted to do something different from the main streme of Archaons-on-foot. So I decided to paint him in the theme oh father nurgle. I'm quite pleased with the outcome, but there's still too much mistakes.
Great idea to do something different with the Big Bad Guy (namely Archaon). But I think color scheme is awful. Just throw away standard WH color schemes and use your pure fantasy, choosing colors you like! That way, your Archaon will look undoubtably UNIQUE. B.t.w. I like the shading-and-highlighting work, and also the green chose for painting the armor.
There are a few things that I think don't quite work. Blue so close to green doesn't work. they are both too close on the colour wheel to have a harmony. And while the armour is well and neatly painted it actually looks too clean and healthy a green to be Nurgle. However you'r work in blending the blues and greens to the highlights is to be commended as blue is not an easy colour to get the right colour balance with. I would suggest that you could add a little purple in washes to the shadows on the armour and this may give the green a more Bruised appearance. Your paintwork is neat and I do like the effect of the sword. :D