Blood for the Baron!

Just seen this Grey Ninja figure in a bulk lot, has anyone seen it before or know what it is?
I don't collect Joes anymore but I don't ever remember seeing a Cobra ninja this colour before.
I have cropped the image but all the other figures seem original with no customs.

It looks like a custom, the eyes look heavily sunfaded so he may have painted it grey to remove the ugly yellowing + the finish looks mat and not shiny like those figures next to it.