The thing is, the official definition (which has changed some time ago) states right now that a deck is a mono deck if it uses cards only from a single element (based on category, ie. card's background, and where do you see it in bazaar, not the cost) and other.
This is of course only a definition, so you can have your own definitions and use them in unofficial events, but during official events like weekly tournaments or when it comes to subforums like these mono-deck subforums, it needs to follow the official definition.
So, I guess someone should move this thread.