While flying, you can turn an enemy attack back on your attacker.

While flying, ground based, targeted attacks against you have their "to hit" reduced by your DEX modifier.

Additionally, if a missile or thrown weapon attack misses, you can use your reaction to make an Acrobatics roll, allowing you to catch it and throw the missile back at your attacker using your normal thrown weapon attack stats. You must have at least one free hand to do this. You can also choose to keep any object you catch in this manner.