Momentum Striker (BoWT)

You understand how to use whip-based weapons to their full potential, granting you the following benefits:

• Proficiency with whips
• Once per turn, you can spend a bonus action with a whip-based weapon to spin up the weapon before making an attack. On the next attack made with this weapon on this turn you deal two additional dice of the weapons base damage (ie a mundane whip would deal 3d4 after spin up instead of 1d4). You can use this bonus action only if you haven’t moved during this turn, and after you use the bonus action , your speed is zero until the end of the current turn
• While you are wielding a whip, other creatures provoke an opportunity attack from you when they enter the reach you have with that weapon.