User blog:Rurhan Nash/Player created classes?

What would is your opinion on player created classes? A few friends and I have been playing a class we call a Shadowcaster, which we play as a subclass of a Rogue. They train in an older dark art that is of bending shadows. Not sure if there is a lore name for this or if it's completely player created, but I wanted to double check that it wasn't breaking any rules before I starting going further into lore on it.