Barbarian: Path of Terror
Barbarians who follow the path of terror draw their rage from the fear they invoke in others. When you are in battle, you feed off of the sheer terror that your strikes leave in your enemies.
Terrorizing Strikes
At 3rd level when you select this subclass, your rage and recklessness in battle invokes great fear in your enemies. Once on each of your turns when you hit a creature with a melee weapon attack while raging, they must succeed a charisma saving throw against a Dc equal to (8 + your proficiency bonus + your strength modifier) or become frightened of you. The creature can repeat the saving throw at the end of each of their turns. Any creature(s) frightened by you no longer have the frightened condition when your rage ends.
Fearmonger
Starting at 6th level, you feed off of your enemies' fear in combat, using it to empower your attacks. Once on each of your turns when you hit a melee weapon attack against a creature that has been frightened by you, you deal an extra (1d8 + your charisma modifier) psychic damage. This extra damage increases to 2d8 at 13th level.
Nightmarish Vitality
At 10th level, you are at your strongest in battle when your enemies are afraid of you. While you are raging, if you end your turn within 5ft of a creature that has been frightened by you, you gain temporary hit points equal to half your strength modifier (rounded down) + your charisma modifier (minimum of 1). If you have temporary hit points from this feature when your rage ends, they disappear.
Dreadful Warrior
At 14th level, you are at your pinnacle of strength when your enemies are terrified of you. When an ally makes a melee weapon attack against a creature that is frightened by you, you can use your reaction to move up to half your movement speed and make a melee weapon attack against that creature. This attack is made with advantage regardless of whether or not you choose to use your reckless attack feature.