ok guys I pulled this idea out of the deepest, darkest depth of my butt while passing a doob around with my buddy who is also into the manga. We both thought it was a pretty cool idea and, even though it a zero chance of happening, we both agreed we'd be satified with whats under kakashi's mask. enjoy, dont hate.

so when someone has a secret it usually leads to at least to one of two things: a bunch of filler/background story or (what im talking about here) a new jutsu that was too powerful to use earlier in the manga. So lets get under the mask already, think of his father Sakumo or "the white fang" why was he called this (I know it was because of his sword but lets choose not to remember that right now). Also remember kakashi's affinity for canines and his abilty to summon those tracking hounds.

Q:whats under the mask already?!
A:His mouth lol, but whats in his mouth? Fangs. White fangs. because kakashi is a werewolf.... or dog sage and when his fangs get exposed to the nature chakra in his surroundings he transforms in to an uncontrollable wolf-beast that is unstoppable. Sakumo also had this same ability except he was in control of his abilities, this is why he was such a feared ninja. do you hoestly believe that a sannin level ninja like Sakumo just has a chakra sword. Could happen.

Honestly I could go along with this if it were to happen. however it would get real old if kakashi started turning into a demon wolf man every fight because the enemies after obito and madara will be too strong. But idk. take it for what it is, its not like this is any worse than everone else's kakashi theories.