You’ve mastered the whip to the point of being able to grapple with them. You gain the following ability:

• When you successfully attack a creature with your whip you can use a Bonus Action to attempt to grapple the target with the whip.
• The target of your grapple must be no more than one size larger than you.
• Roll a contested grapple check. Your Dexterity + Proficiency Bonus contested by the target’s Strength (Athletics) or Dexterity (Acrobatics) check (the target chooses the ability to use).
• If a creature is successfully grappled in this manner it is also considered restrained for the duration.
• A grappled creature can attempt to escape the grapple in the same way at the top of each of it's turns.
• A whip can only grapple a single creature at a time.