You’ve developed the skills necessary to utilize a whip for grappling. You gain the following benefits:

• You gain proficiency with whips.
• You may use a whip, rather than an empty hand, to grapple. You must make a DEX(Acrobatics) check with advantage contested by the targets choice of DEX(Acrobatics) or STR(Athletics).  You can't use the whip to make melee attacks for as long as the target remains grappled, and may release the grapple at any time.  The grapple also ends if you aren't holding the whip.
• While using your whip to grapple a creature, shoving a creature requires you to make a DEX(Acrobatics) check rather than a STR(Athletics) check, and can only knock them prone.
• You have advantage on attack rolls against a creature you are grappling.
• You can use your action to try to restrain a creature grappled by you. To do so, make another grapple check. If you succeed, the creature is restrained until the grapple ends. Once restrained in this way, you can't use this whip but no longer need to hold it to maintain the grapple.