Path of the Nightmare
Path of the nightmare are barbarians who are so racked with negative emotions and dark nightmares that it affects their form when they rage.
When these barbarians rage their form is twisted into a being of shadow with wicked evil eyes and twisted black limbs. Their form while raging is so utterly terrifying that most people who see this form would prefer eldritch horrors.

Being of nightmares
Starting at the 3rd level, when you enter your rage you take on a dark and twisted form that makes even the surliest of people cower in fear. When you enter your rage each creature within 10 feet of yourself must make a wisdom saving throw against your nightmare save, taking 1d8 psychic damage and gaining the frightened condition until the end of their next turn on a fail. In addition while you rage, you may use a bonus action to invigorate horror in those around you, forcing each creature to make a wisdom saving throw against your nightmare save, dealing 1d4 psychic damage to any creature within 5 feet of yourself on a fail.

Your nightmare save is equal to 8 + your proficiency bonus + your strength modifier.

Master of fear
Starting at the 3rd level, you gain expertise in the intimidation skill (meaning you double your proficiency bonus to checks made with the skill).

Cloak of night
Starting at the 6th level, you can use a bonus action to cloak yourself in shadow gaining a bonus to stealth checks equal to your proficiency bonus and allowing you to take the hide action, even if you cannot hide behind anything.

You cannot run from fear
Starting at 10th level, when a creature takes the disengage action and moves out of your reach you may use a reaction when the creature ends their movement to teleport to them and immediately make a single melee weapon attack. You may also do the same thing if a creature would provoke an opportunity attack by moving away from you.

Utter terror
Starting at the 14th level, once per short or long rest when you enter your rage, you can optionally gain the benefit of either the Enlarge/reduce spell, the Blur spell, the invisibility spell or the Spider climb spell. These benefits last for either the next minute or until your rage ends.