What can be classed as OP?
"Anything that is player-controlled can be seen as OP if it’s too good in the current version of a game. Characters, weapons, and skills are the most common suspects for being labeled as OP if they’re noticeably better than the other options in their category."
This, in my opinion, has happened to master dual wield weapons when you use rending slashes or blood craze, the dmg is too much and you see it everywhere now, its too good not to use.