When falling from any height, you instantly descend up to 50 feet. If you're still falling on your next turn, you descend up to 150 feet at the start of that turn and 300 feet at the end of that turn.
If you're still falling on any turn after that, you descend up to 500 feet at the start of your turn. 500 feet at the end of your turn, for a total of 1000 feet per turn.
A creature can choose to, as an action, increase or decrease the end of turn descent rate from between 500 feet to 1000 feet per turn.
At the end of a fall, you take 1d6 bludgeoning damage for every 10 feet you fell, to a maximum of 100d6. You also land prone, unless you somehow avoid taking damage from the fall.
A flying creature falls if its knocked prone, its flying speed is reduced to 0 feet, or if it otherwise loses the ability to move, unless it can hover or it is being held aloft by magic.
Many flying creatures have a better chance of surviving a fall than a non-flying creature does, simply by having their anatomy constructed for it. These modifiers can be applied if one see it fit when calculating falling damage:
- Reduce the amount of feet by the creature's current flying speed. Simulating a conscious creature taking measures to slow its fall.
- Reduce the amount of feet by the creature's normal flying speed. Simulating a creature with hollow bones, like many small birds.
- Modify the falling distances per turn by for example: one half, one fourth or one fifth. Simulating creatures with very low terminal velocity thresholds.