ATTENTION!: THIS IS A GOLEM SKIN, not a PLAYER skin, so if anybody would like to re-skin their golems, or put this skin in Custom NPCs, feel welcome to do so, but don't try to apply this to yourself. In case if you want to change the default (vanilla) skin of your Golem, look in the comments below. The link is in the end of the description.

Warning!: This is just a plausible explanation and does not refer to any mod or texturepack known of.

"The Ancient Protectors of Minecraftia, these lead, covered in mystical runes, Golems, lived in the Precursor Villager Age, a time that is very little known of, with the only artifacts remaining from this mysterious era being the Ender Crystals and these Precursor Golems.

Link: lh3.ggpht.com/bfJq8YCin07AcD_W1-X9cFBmEIHSpNnxOuskaOQqYJVHWb_m5vVD2LhUCR8XRE4MnbP58yZlcsssXzO_VUsUBg