MOB is one of the most popular 5on5 flag football plays where handoffs & running are allowed, as it is extremely versatile, simple and effective. Almost every team you face will switch to a zone flag football defense against a 4 bunch formation, typically a 2-2 or 3-1, which makes handoffs & throwbacks more difficult to cover, and also makes it easier for a good quarterback to find windows for throwing the ball.
Like many 5on5 flag football plays out of a bunch formation, this one starts with the quarterback under center, who then immediately fakes or directly hands off to  who now has the option to throw or run. His immediate options are to hit the quick out with  if left uncovered for an easy 10 or so yards, or hit  on a banana or corner route finding a gap in coverage between the corner and safety. The center just does a simple curl, and if the backside corner doesn’t squeeze down to help out, the center very well could be wide open for another easy gain. If the rusher doesn’t kill  on the handoff, he can very easily let the routes develop for a second and take off running, now having the center and  in pitch position. If the rusher does kill him, and nobody kills the original quarterback, he can easily throwback or hit him on a wheel all by himself down the left sideline.
The beauty of this play is that you can use it anywhere on the field, including on the goal line where there’s not an option to run but it’s still very effective. You can also come back to it often as there’s not a great way to defend it every time (although here’s some tips for defending a bunch offense in 5on5), and you can tweak the routes just enough to cause confusion or catch the defense guessing. For instance, change the corner flag football route to a corner post, have the  snag and fake the handoff to  having him drop into a star throwback option on the right. The first 3 seconds of the play looks identical, but the result is quite different.
Give it a try in your next league or tournament and let us know what you think in the comments below! Also feel free to check out more of our 5on5 flag football plays here!