Path of Madness

Barbarians who follow the Path of Madness derive power from hysteria. Though they are certainly physically strong, their true strength is bolstered by their mental rage at having been exposed to something truly horrifying. Be it a reality-warping influence from the Far Realm, an eldritch entity residing on the Material Plane, or a wellspring of forbidden knowledge that has driven the barbarian insane, those who seek this path know that if their mania takes control of them, the consequences would be dire. But some already have nothing to lose, and would surrender their mind to forces beyond their reach to pursue their goals. Drow, half-orc, and even mind-flayers have been known to pursue this path to wreak havoc on an unsuspecting world. 

Mental Might

Starting at 3rd level, when you enter your rage, your allow your mind to become corrupted with the fear of what you have seen, enhancing your body. You have proficiency with Wisdom Saving throws while in your rage.

Your mental impurity transfers to your weapons as well. You can add 1d8 psychic damage to a damage roll for one attack during your turn. When you reach 10th level, the damage increases to 2d8, and when you reach 14th level, the damage increases to 3d8.

Eyes of Dread

At 6th level, your fear and madness can spread to others. You have advantage on Intimidation checks.

In addition, you can use an action to lock eyes with an enemy and use this feature. The enemy must make a DC 17 Wisdom Saving Throw. On a failed save, they take 4d6 psychic damage and are frightened until the start of their next turn. On a success, they take half damage and are not frightened. The damage increases to 6d6 when you reach level 12 in this class.

You can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses of this feature when you finish a long rest.

Coiling Horror

At 10th level, the unearthly forces start to leak from your mind. You can use an action to touch the ground and cast Black Tentacles at 4th level without the need for any components or Concentration. However, the spell only lasts for 30 seconds. The DC for the saving throw is your STR modifier + WIS saving throw modifier + 10.

You can use this spell a number of times equal to your proficiency bonus, and you regain all uses of this spell when you finish a long rest.

 

Insane Obliteration

At 14th level, you can utterly surrender your soul to the unspeakable horrors that lie within. When you enter your rage or at the start of one of your turns during your rage, you can choose to activate these effects at the cost of one level of exhaustion when your rage ends:

-Your AC increases by 3, and you gain or regain 2d10 hit points. The release of inhibition from your mind increases your fortitude.
-Your weapon attacks score a critical hit on a roll of 18-20. In addition, any creature you hit with a critical hit is frightened until the start of their next turn. The brooding of the wicked whispers makes your attacks stronger.
- You can use an action to unleash a scream from the depths of despair. All hostile creatures within a 20 foot radius must make a Wisdom saving throw. On a failed save, the creatures take 3d6 thunder damage and are stunned until the start of their next turn. The eldritch forces in your mind have more power over foes.