Seconding MysteryMeat.
I don't think the contrast between the green and blue was a
direct issue. Mostly the problems are
with each colour. The lack of hue-shifting and unity I mentioned is the only one that ties into contrast between the green and blue, but to describe that as a contrast issue is to misunderstand the problem.
Colours can contrast in three ways:
- their values, one can be dark while the other is light
- their saturation, one can be dull/grey, the other can be saturated
- their hues, e.g. yellow and blue contrast more than yellow and orange (at the same value/saturation, anyway)
In this piece, the value contrast is fine (maybe even a little low!). The saturation contrast was low because everything is over-saturated. This is where MM's analysis of the two colours clashing comes from.
The hue contrast is
fine.
However, if the shadows are hue-shifted towards each other, that would leave the main shapes the same colour that they were (and therefore contrasting the same), but just the shadows would contrast a little less. This would be a contrast change, yes, but it wouldn't be one most people would immediately think of as a contrast change. Instead, it would just feel like the skin and cape exist in the same world, affecting each other.
Edit of MM's edit, with the two darker cape colours shifted towards green, and the darkest skin colour shifted towards blue (compared to the original):
(However, note that I also lowered the saturation and value on the mid blue slightly. This actually
increases the contrast with the greens, but the lower hue contrast makes up for it. Starting to see why this isn't really a contrast issue?)