They say that defense wins championships but, for me, I'll take a high-octane, point-scoring offensive machine any day. Whether it's a beautifully thrown long bomb by Ben Roethlisberger to Antonio Brown or a perfectly-blocked run by David Johnson, there's just something satisfying watching a well-crafted offensive unit.

But exactly which offenses topped the league in 2015?

To answer this question, I turned to our signature metric over here at numberFire, Net Expected Points (NEP). For those unfamiliar, NEP measures the contribution of a play to a team's (or player's) chances of scoring. If you contribute to your team's chances of scoring above expectation you receive a positive NEP, and a negative score when you do the opposite.

So with that being said, who were the best offensive squads in 2015?