You have mastered your technique with the whip and have learned to take advantage of every drop in any enemy's guard, gaining the following benefits:

• When you hit a creature with an opportunity attack, the creature's speed becomes 0 for the rest of the turn.
• Creatures provoke opportunity attacks from you even if they take the Disengage action before leaving your reach.
• While you are wielding a whip, other creatures provoke an opportunity attack from you when they enter the reach you have with that weapon.
• You gain Expertise with the whip.