You focus on a deep and unspoken connection with your mount, lending it strength and working together as one.

You summon your mount to your side.

When you have become separated from your mount but can see it, you can use an action to whistle. As long as your mount is able to hear you, it uses its reaction to move until it is adjacent to you. 

Your mount makes an incredible leap, soaring through the air.

When your mount makes an Athletics check to jump, you can use your reaction to grant it a fly speed equal to half its Speed until the end of your turn. Your mount can only fly in a straight line.

Under fire, you dive for cover.

When you are targeted by a ranged attack, after it hits or misses you, you can use your reaction to move up to your Speed. 

If your movement ends adjacent to either a solid barrier as big as you are or a creature the same size as you or larger, until the beginning of your next turn you have three-quarters cover against ranged attacks (+5 bonus to AC and saving throws) as long as you remain adjacent to the barrier or creature.

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.

You set yourself firmly against maneuvers.

You strike a spellcaster and disrupt their control over magic, fracturing the power behind a spell and transforming the energy so it roots them to the spot.

You charge a spellcaster in order to interrupt their spell.

When a creature you can see casts a spell, you can use your reaction to move up to your Speed. If you end your movement adjacent to that creature, you can make a melee weapon attack against it. On a critical hit, the spell is interrupted (expending the spell slot) and has no effect.

The battle around you narrows as you focus your ire on a single opponent, ignoring other threats or enemies.