Curse of Strahd
From Explosion Rodeo
Plunging damage: codified as using an action from moving into an open space at least 10 feet above a target: make a melee attack roll. If you are more than 30 feet above the target, you have disadvantage on the attack roll. If you hit, you transfer all of what would have been your falling damage to the target, added to your normal melee attack (1d6 per 10 feet). If you miss, you are proned and take falling damage normally, the enemy creature may choose to move 5 feet and place you in their prior location, or place you in a square of their choice adjacent to their current location.