You tune your senses, focusing on the fight at hand.

You and your allies combine forces and attack a single foe with devastating results.

Make a melee weapon attack against a creature. Any willing ally within your reach can use their reaction to make a melee weapon attack against the same creature. 

If the creature is hit by two attacks, it takes extra damage equal to your proficiency bonus. 

You offer inspiring encouragement to an ally and they gain their second wind.

When an ally you can see takes damage from an attack, you can use your reaction to release a hearty rallying cry. As long as they are able to hear you, your ally regains an amount of hit points equal to twice your proficiency bonus.

By focusing on keeping enemies off-balance, you help allies attack more effectively.

Whenever you hit a creature with a melee weapon attack, you can also take the Help action. On a critical hit, the target of your Help action can use their reaction to take the Dodge action.

You interpose yourself to take a hit for your ally.

When an ally within your reach is hit by an attack, you can use your reaction to swap places with them and become the target of that attack, taking half as much damage as normal.

You throw your ally at an opponent, lending them extra power.

You and an ally tackle a foe together, your combined strength forcing them to the ground.

Choose an ally you can see. Your ally can use their reaction to move up to 20 feet to be adjacent to a creature you designate. 

No matter how far away a foe is, if you can see them they’re still in danger.

You can literally hear the sound of incoming missiles and react to them easily.

Until the end of your next turn, you gain blindsight to a range of 20 feet. When you are hit by a ranged attack, you make a Perception check against a DC equal to the attack roll. 

On a success the attack misses you, and on a critical success you redirect it back at the attacker.

You repeatedly charge your mount at your opponent, attacking again and again.