I might be delusional but whatever. So I was rewatching that scene in s3p1 where Cole has an incredibly deep voice and I realised that he was looking at a weird stone. Now this stone had some symbols.
The oni symbols from earlier in the season.
And the fact that he knew something was happening that wasn’t the mergequakes like Geo says.
This combined with everything that comes in s4, him being able to use not only one half of the weapon but the full weapon of desolation, makes me think too much.
Maybe I am truly delusional, but the chances of oni Cole being real just got higher (not much, but remember that nothing in animation is done with no purpose)















