Djem So

Masters of this form focus on wearing tough opponents down with strong parries and quick counterattacks. This form allows one to attempt to dominate their foe offensively and defensively, pushing their opponent to their limit.

Ability Score Increase. Choose to increase either your Strength, Dexterity, or Wisdom by 1.

Duelist's Stance. While wielding a melee weapon, you may take a bonus action to take a Duelist's Stance. While in this stance, your AC increases by an amount equal to half of your Proficiency Bonus. This stance ends at the start of your next turn, or until you make an attack of opportunity. You may enter this stance a number of times equal to half of your Proficiency Bonus. You regain all uses of this feature on a Short Rest. 

Parried Strike. When a creature misses you with a melee attack, you may end your Duelist's Stance as a reaction to make an Opportunity Attack on the creature who missed you with that attack. You have advantage on this attack, and if the attack was a melee weapon attack or an unarmed strike, it scores a critical hit on a roll of 18-20 on a D20.