When you fall:
- You take damage: 1d6 bludgeoning damage for every 10 feet you fall, to a maximum of 20d6.
- You land prone.
Rate of falling
- 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.
A flying creature falls when:
- it is knocked prone
- its speed is reduced to 0 feet
- if it loses its ability to move, unless it is aflight due to magic (like the fly spell)
When a flying creature is knocked prone
- It falls 500 feet minus its flight speed before calculating falling damage
- Next turn, it can take its action to "stand up" and fly.