Pretty much my thoughts exactly, Mal.
Too much noise, in terms of color, for this to be a great fake.
Some of your lines stand out too much as well. The outline around Ermacs flap thingy (anyone know what the hell thats called btw?) and in the shot of the sprites, all the gold and black piping on Kobra's Gi.
Not enough shadowing on the sprites. Ermac looks a lot better on the pink background because it is bright, so the shading shows up more. In the fake, He looks to be a bit flat. There doesn't seem to be a noticeable source of light. Basically, make the dark parts darker and the bright parts brighter.
Kobra's shadow is in the wrong spot too (sorry, the more I'm actually looking, the more I'm seeing that could use some tweaking). If Ermac's shadow is being cast backwards, then the light is coming from the front. If the light is coming from the front, there is no way that Kobra's shadow could start where it does (on a plane in front of Ermac's). From the look of things, the shadow should start between the second and third board in to the pic.
Your blood looks pretty stellar. The fact that you have Ermac controlling that as well doesn't
I know that's how the picture you did this off of looks, but for this pic, it just adds more of that green noise.
This style is really reminiscant of MaxDam. I hope I don't offend by asking, did you take chopped up renders of the characters from MKD and place them how you needed or did you just fill in a shape with color, then do all the detailing to that?
Either way, it's still some of the best stuff we've seen 'round these parts lately.
Kudos