If i had to define OP in the way that i mean it, I would say that it is a rule, model, or scenario that causes a breakdown in the game or causes the game to no longer be playable. This would not include players needing a higher level of skill nor would it include greater and more in depth levels of strategy.This would include but not be limited to, an infinite loop, an auto win, contradicting rules, and other things along this line, which as stated with auto win would include Unbeatable.OP should not be used to describe " Really really hard." I would use "[url=http://define.com/rendered] Rendered powerless especially by an excessive amount or profusion of something." Though he would be OP by the definition " Having more than the required power", but at that point there are defiantly more master than Hamelin that meet that definition.