Grappler+

You’ve developed the skills necessary to hold your own in close-quarters grappling. You gain the following benefits: 

You can make a grapple check as an opportunity attack.  

In addition, you gain the following grappling maneuvers: 

Head Smash. You may use an attack action to try and stun a creature grappled by you. To do so, make another grapple check. If you succeed the target must make a constitution saving throw equal to 8 + your proficiency modifier + your strength modifier or be stunned for one round. 

Sleeper Hold. When you are grappling a creature that is not grappling you and you have a hand free, you can make another grapple check to establish a sleeper hold. This replaces one attack as part of an Attack action. As long as the creature remains grappled, when it starts it turn, it takes bludgeoning damage equal to 1d10 + your Strength modifier. You can use this maneuver while you have no hands free by going prone. 

Throw. When you are grappling a creature that is not grappling you, you can throw it, dealing damage to the creature and whatever you hit with it. You can make another grapple check to make a melee attack (as part of the same action) against a creature or object within your reach, or a ranged attack using your Strength modifier against a creature or object within 10 feet. This ends your grapple and leaves the grappled creature prone in a space adjacent to the second target. On a hit, the creature you were grappling and the second target take damage equal to 1d4 + your Strength modifier + your proficiency bonus, and the second target must make a Strength saving throw, falling prone on a failure. On a miss, only the creature you had grappled takes this damage.