CQC

You have mastered the recently developed art of CQC, this style of combat allows you to grapple, restrain and otherwise dispose of your enemies while wielding a knife and a pistol.  You gain the following benefits.

Increase your Dexterity Score by 1 to a maximum of 20.
Substitute your Dex modifier + your proficiency bonus for strength on a grapple check. Grappled creatures have disadvantage on checks to break free.
You can use a Bonus Action on your turn to restrict airflow to a grappled target. If the target is your size or smaller, it must make a Con save contested by a  DC of 8 + Dexterity Modifier + Proficiency Modifier  or lose oxygen. If a creature fails this roll a number of times equal to their Constitution modifier (Minimum of 1), they are unconscious unless there is a reason for them to remain awake.