Think Ancient Ogre of the Tekken series.
It's not paint.
Yep. I've looked at him pretty closely and noticed he looks a bit "crusty". Looks like some sort of paint to me as well.
As far as light shining through the paint goes..hes a god. God of the sun. He can do whatever he wants lol
Well, human skin isn't always perfectly uniform in color
My bad, Ledbetter. But I'm not saying the markings on his body aren't tattoos or scars. I actually believe that's what they are. I'm talking about the green coloration covering nearly his entire body. That there looks like it could be paint - perhaps war paint, or something along those lines.
Oh, sorry, maybe I misunderstood.
Well, anyway, Kotal Kahn seems to be based on Huitzilopochtli (already said that on other thread), who is the War/Sun/Sacrifice god of the Aztecs, functions that match exactly on his variations. Even though he has a Quetzal's head as his helmet, feathers and snakes (which resembles another god, Quetzalcoatl, known as "the feathered serpent"), it's more likely he is Huitzilopochtli.
And here is Huitzilopochtli:
And his skin is green on almost all the representations. Quetzalcoatl the same, when on his human form.
I think he probally had both, you know, Mesoamerican cultures did have the body painting culture, but I think most gods are not on the same color as humans, specially mayans, who loved a jade-green colored thing.