#4 The New Day
Well, you know what they say - opposites attract. Not many factions are more unpredictable than The Shield, but The New Day may just take that crown!
While The New Day's singles success doesn't measure up to The Shield's by any stretch of the imagination, very few factions have had quite as much success as a team than the current and five-time SmackDown Tag Team Champions. While The Shield have all held Tag Team Championships, all three haven't done so at once - like The New Day with their Freebird rule that allows any two of the three to compete at any one time.
When it comes to popularity, too, this one would definitely be a close call, and nothing short of a dream match - or a dream rematch, following the trios' clash at Survivor Series last year.
Yet again, we have some great match-ups within the dynamics of these trios. With one side on Raw and the other on SmackDown, could Survivor Series signal the sequel for these giants to collide?