Path of the Warhorn

Barbarians set on the Path of the Warhorn choose a style set on striking fear into enemy forces or rallying their allies to charge into battle. Use your own booming voice to shout commands or insults towards any foes, or blast the sound of your chosen musical instrument.

Horrors of Battle

When you take this subclass at 3rd level, your natural affinity for battle outwardly shows to those who witness you. You gain proficiency in the Intimidation skill if you do not already have it. Also, any creatures intimidated by you can't use their movement speed to move towards you.

Martial Music

At 3rd level, your voice can now be projected at will to be three times as loud as normal. You also gain proficiency with three musical instruments of your choice.

Rally the Troops

Starting at 6th level, you can use a bonus action while raging to make a performance check using an instrument that you are proficient in. Any allies within 60 feet and can hear you, as in not under the deafened condition, gain temporary hitpoints equal to your race damage bonus and can then move up to their movement speed without provoking attacks of opportunity. You can use this feature a number of times equal to your Constitution modifier.

Sound of Conquest

Beginning at 10th level, you can use your action to frighten someone with your menacing presence. When you do so, choose any amount of creatures of an amount equal to your proficiency bonus within 60 feet of you. If the creature can hear you, it must succeed on a Wisdom saving throw (DC equal to 8 + your proficiency bonus + your Charisma modifier) or be frightened of you until the end of your next turn. On subsequent turns, you can use your action to extend the duration of this effect on the frightened creature until the end of your next turn. This effect ends if the creature ends its turn 60 or more feet away from you. If the creature succeeds on its saving throw, you can't use this feature on that creature again for 24 hours.

Roar of War

When you reach 14th level, the very sound of your blasting music or booming voice begins to harm enemy forces. While using your Rally the Troops feature, you may make an Intimidation or Performance check contested by the individual Wisdom checks of an amount of enemies within that range equal to your proficiency bonus. Any enemies who do not succeed on their check take thunder damage equal to your barbarian level, or half that damage on a failed saving throw.

Credits

Image- Wikipedia: Olifant or Hunting horn in Ivory Fourteenth Century From an Original existing in England