Path of the Abomination

Your physicality begins to mutate as the influence of an eldritch horror begins to penetrate your body. In your rage, the balance of control over your form tips toward the horror, causing you to take on a gruesome visage. 

As an Abomination barbarian, you decide the source of your powers. Consult the Abomination Origins table for a possible origin of your power:

Origins of Abomination:

d4	Origin
1	You are the victim of a conjuration spell gone horribly wrong. Your sweat is a vibrant purple ooze.
2	A cult to attempts to create heralds to their gods by transfusing your blood with that of a long dead slaad. Your skin hardens and tongue grows when angered.
3	You were implanted with a mind flayer tadpole, but instead of complete ceremorphosis, the developing tadpole shares a symbotic relationship with you. You constantly hear voices that provoke your rage.
4	You are a beholder's anger at adventuring parties made manifest. Eyes will briefly appear on your body when no one is looking directly at you.

Violent Mutation

When you enter a rage, several appendages (the form and number of appendages are up to you) erupt from random places on your body. Every creature within 15ft must make a Wisdom saving throw (Save DC = 8 + your proficiency bonus + your Constitution Modifier). On a failure, the creature becomes frightened of you for a minute. Each creature may repeat the saving throw at the end of each of their turns. 

In addition, after you hit a creature with a melee attack on your turn, you can then try to grapple the target as a bonus action (see the Player's Handbook for rules on grappling). 

Consuming Flesh

If the creature remains grappled on your following turn, the creature instead becomes restrained, as your appendages begin to overwhelm the creature. 

In addition, your joints unnaturally dislocate and extend, giving your attacks the reach property. 

Ghastly Progression

You gain resistance to psychic damage.

In addition, when you enter your Violent Mutation, your body begins to reveal additional body parts from creatures of the far realm. You may choose one of the following abilities:

Slaad Claws: you gain two times your Barbarian level + Con Mod in temporary hit points. When you successfully hit a creature with an attack, that creature cannot regain hit points until the end of your next turn.

Eyes of Beholderkin: you gain a hover speed equal to your walking speed. If you are the target of a magical effect that forces a saving throw, you have advantage on the saving throw.

Mind of the Star-Spawn: you are immune to psychic damage. At the start of each of your turns, each creature within 5 feet must succeed on a Wisdom saving throw against your spell save DC or take 3d6 psychic damage. 

Localized Singularity

Your rage unleashes a wave of psychic pain and terror. As an Action, you can allow the horrors within to overtake your body. All creatures within 30 feet must make a Wisdom Saving Throw against your Spell Save DC. On a failure, the creatures take 5d10 psychic damage (half as much on a save) and are stunned. Each creature can repeat the save at the end of their turns.

If the creature is already restrained by your Consuming Flesh ability and fail their save against the Localized Singularity, the creature becomes incapacitated and is absorbed into your body. They then begin to suffocate. This requires your Concentration; and the creature is no longer incapacitated if you lose Concentration. 

You can only use this feature once per long rest.