Increase your Wisdom, intelligence, or Charisma by 1, to a maximum of 20.
You have to be proficient with magic to use this feat.

Once per turn when you hit a creature with an attack that deals slashing damage, you can reduce the speed of the target by 10 feet until the start of your next turn.
When you score a critical hit that deals slashing damage to a creature, you grievously wound it. Until the start of your next turn, the target has a disadvantage on all attack rolls.