Pankratiast

You are highly trained and proficient in the art of empty-hand submission fighting.

• Your unarmed strike uses a d4 for damage.
• When a creature is grappled by you and you succeed on an additional grapple attack, the creature you are grappling begins suffocating. If this grapple attack fails, then the grapple is broken. Breaking the grapple also ends the suffocation.
• When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to grapple or shove the creature, rather than making an opportunity attack.