Ultimate Beast

You master the art of shapeshifting into animals.

You can become a huge beast.
You can become a flying beast.

If you are prone while flying, you are immobilized, unless you have the ability to float.
If you are immobilized while flying, you begin to fall, unless you have the ability to float.
If you can fly, you may spend an action while falling to end the prone condition (and accompanying immobilization and falling), if you are not also immobilized for another reason.

Falling:
A creature falls up to 500 ft. per round, at the end of its turn.
At the end of a fall of 10 ft. or more, a creature takes 1 blunt damage for every foot that it fell, up to a limit of 500 damage.
A creature which takes 100 or more damage from a fall may instantly die at the Headmaster’s discretion.
A soft landing area or other mitigating factors may reduce this damage.