Would flying a grappled character hard into the ground deal them extra falling damage?

Question

Trying to figure out the mechanics of a certain situation. PC grapples enemy and uses a move that doubles movement speed. Following that, a stacked move allows the PC to carry grappled enemy 60 ft into the air. In this situation the PC has an added benefit of not taking falling damage. The goal now is to force the grappled enemy to fall with the PC into a 60 ft slam. Would added flying movement downward add to damage? Also, if using flying to assist the slam, would that remove the benefit of no damage while falling for the PC?

Backround info: PC is a Mystic under Order of the Immortal, using the Body of Wind Discipline which grants no fall damage and ignores difficult terrain just with the Psychic Focus. Also in Body of Wind, Mystics can spend Psi points to gain 20ft of flying speed per Psi point used up to 3.

Answer 1

Id love to go in to the physics reasoning as to why this may work, but unfortunately your character is in the DnD world and physics doesn't always apply. The short answer to your question is No (flying a grappled target harder into the ground would not do extra fall damage).

The reasoning is twofold - grappled targets and falling/falling damage.

First moving a grappled target (from PHB pg195):

Moving a Grappled Creature. When you move, you can drag or carry the grappled creature with you, but your speed is halved, unless the creature is two or more sizes smaller than you.

So your speed is probably halved when you are flying with the target. This has nothing to do with difficult terrain.

But more importantly (and even if your speed wasn't halved), at 60ft per move (120ft double move/round, which is 6 sec), you are traveling at 20ft per sec or about 14 miles per hour. When you are falling, falls are instant or at terminal velocity (this is DMs call as we are in the DnD world not earth), but in a nut shell, you fall much faster than you can slam someone. Thus there is an argument for taking less fall damage by flying someone into the ground than if you simply dropped him from that height.

Answer 2

Your PC has two options:

1. Fly straight at the ground and "slam" the opponent. This will result in nothing happening except you've used a bunch of movement to fly high, then more movement to get close to the ground. D&D 5e has no concept of momentum, so any momentum gained by flying downward at a high rate of speed will not be imparted on the grappled opponent and thus will not result in actual damage when he is released. His damage will be falling damage taken from the height at which he was dropped/released from the grapple (assuming he is released at the last possible moment, 5ft and no falling damage).

2. Fly up high and release the grapple. This will ensure the PC's opponent takes maximum falling damage (6d6), and will be a much more effective use of his actions in a given turn.

Answer 3

No, there is no rules mechanic for this

The mechanic we have for impact damage from high speed is falling damage, with 1d6 per 10 feet fallen, to a maximum 20d6. Falling damage is defined by height, not by speed. Xanathar's Guide to Everything clarifies that

The rule for falling assumes that a creature immediately drops the entire distance when it falls.

How fast you fall is not explicit in the basic rules, and according to the clarification the speed is infinite ("immediately ... the entire distance"). Xanathar then offers an optional rule that

When you fall from a great height, you instantly descend up to 500 feet. If you're still falling on your next turn, you descend up to 500 feet at the end of that turn.

So falling speed is still infinite, as the falls happen "instantly" or "at the end of the turn", taking no time.

OK, but what if we assume a falling speed to compare against?

Of course, infinite speed makes no sense. What if we interpreted the optional rule as a falling speed of 500 feet per turn, which we know to then deal d6 damage per 10 feet on impact?

Normal fly speed is also only 60 feet per second, and if you drag along a grappeled creature, speed is halved, so even after a Dash action to double it again, you would still be at 60 feet per round. This is the falling speed of Feather Fall which we know to not deal any damage on impact. So still no damage.

Wait, what if we were really fast?

What about a rogue that has all of fly, longstrider and haste cast on them in order? Fly gives them a 60 feet speed. Longstrider increases it to 70 feet. Haste doubles their speed to 140 feet. They gain one extra Action from haste, and a Dash bonus action from being a rogue, for a total movement with their normal Dash action and Move action of 4 x 140 feet = 560 feet. That would be even faster than falling speed. However, dragging the creature along will half their speed to 280 feet.

In that case, since the kinetic energy that would be causing the damage on impact grows with the square of the speed, about half the speed would translate to about quarter the potential damage. With an expected 3.5 points per die, this would leave maybe one point of damage per die.

So, unless the opponent has the ability to fly themselves, you would be much better off to drag them up, then let them drop for falling damage. Especially because there are also no clear rules for adjucating how slamming the other creature into the ground would buffer the damage of your own impact.

PS. A word on real world falling speed

As explained in other posts, under planet earth gravity and air resistance conditions, a human falling accelerates quadratically to fall 576 feet in the first round, and up to a terminal velocity of 1,043 feet after the second round. D&D for ease of play does not simulate the physics of acceleration during falling.

Answer 4

Straight from a physics perspective, if the flight is winged in benefit, then it would be a straight physics fall. So in a straight physics argument, I'd say you get no extra falling damage benefit for your PC's flying on downward decent. That's just gravity and your PC's mass (dependent on how we interpret the body of wind discipline's no fall damage caveat).

I see you have two options:

• the wind catches him. Ergo no damage to the enemy, they fall 60 ft but then get caught by small puffy cloud.
• He turns partially or wholly into Wind. Then he needs to defend how he can maintain a hold onto enemy.

From my interpretation of the no fall damage, I'd consider it a matter of the body. The wording of "Body of Wind" suggests the ability is a psychic ability that translates the body into a part of wind eliminating fall damage.

As for a 'slam.' Not quite a body slam, but more one body landing from a 60 ft drop.