You use your mount as a shield.

You must be mounted to use this maneuver. 

When a creature targets you with an attack you can use your reaction to swing down the side of your mount, making it the target of the attack instead of you. 

In tune with your mount, you guide it to greater heights.

With incredible swiftness you tear your weapon from its sheath and let fly a reckless attack.

With awe-inspiring skill you unleash a thrown weapon or arrow, knocking a missile out of the air.

When you see a missile from a ranged weapon attack enter into the normal range of a weapon you are wielding, you can use your reaction to deflect it. Use a weapon to make a ranged attack against an AC equal to the attack roll of the missile. On a hit, the missile is deflected and misses its target. 

At the Narrator’s discretion, certain ranged weapon attacks (like a giant’s thrown rock) may be too heavy to be deflected by Countershot.

Badly wounded, you force yourself to keep fighting.

When you are reduced to 0 hit points, you can use your reaction to regain hit points equal to 1d12 + your proficiency bonus + your Constitution modifier (minimum 0). 

You wield your weapon with abandon, striking seemingly at random.

When you miss with an attack using a weapon that has the heavy property, you can use your reaction to make an attack with the same weapon against another target within your reach.

You power through your enemy’s special attacks.

At the edge of death, you cling firmly to life.

A powerful blow smashes a weapon from your enemy’s grasp.

Girding yourself when your body is assaulted by more than clenched fists or sharp steel, you defy weakness and overcome.