As an action while flying, you can use the Dash action. If you move at least 3 meters in a straight line angled downwards toward a creature, you can make an Attack action with a melee weapon attack against it.
On a hit, add the stamina die to the attack’s damage and you don’t provoke opportunity attacks when you fly out of the creature’s reach.
On a critical hit, add twice as much damage.
On a miss by 4 or less, add half as much damage.
You can increase the damage for each additional stamina die expended.