Path of the Forgotten

By taking the Path of the Forgotten as a Barbarian, you have accepted a portion of an ancient, long-forgotten entity within yourself.  When Raging this bond manifests as your otherworldly armor, a sheathing reflective of the entity with which you have bonded yourself.  It could be chitinous plating, ethereal armor, petrified bark, or whatever you and your DM find fitting of the long-Forgotten entity.

Level 3: Otherworldly Armor

You learn to channel the power of an otherworldly entity through your very form, magically covering your body in chitinous plating, ethereal armor, petrified bark, or something reflective of the source of your power.  While your Rage is active, you gain a +1 to your Armor Class.

When you reach 14th level in this class, the Armor Class bonus increases to +2.

Level 6: Lashing Reflex

Your otherworldly armor becomes reflexive to when you are attacked. If you are raging and a creature hits you with a melee attack, you can use your armor to make a special weapon attack against the attacking creature after its attack once per round.  This attack uses your Constitution modifier plus Proficiency Bonus to hit and deals 1d10 bludgeoning, piercing, or slashing damage (your choice) on a hit.  This does not use your reaction and the damage is considered magical for the purpose of overcoming resistances and immunity to nonmagical attacks.

When you reach certain levels in this class, the armor deals more damage: by 2d10 at 10th level and by 3d10 at 14th level.

Level 10: Protective Instinct

At 10th level, your otherworldly armor becomes more protective of your allies to danger as well as helping you move around the battlefield.  When a creature hits a melee attack against an ally within 10 feet of you, you can use your reaction to force that creature to reroll if the ally and creature do not have full cover from you. Alternatively, you may instead pull the creature towards you or yourself towards the creature after the attack is made.  These movements do not provoke opportunity attacks.

You can use this feature a number of times equal to your Constitution modifier (minimum of once). You regain all expended uses when you finish a Long Rest.

Level 14: Lash Out at All

With your connection deepened, you can cause your otherworldly armor to lash out at enemies in all directions from you.  You can use your action to cause your armor to lash at each creature of your choice within 20 feet of you.  Each creature of your choice must make a Dexterity saving throw (DC 8 plus your Constitution modifier and Proficiency Bonus) or take 4d10 bludgeoning, piercing, or slashing damage (your choice).