Path of the Gief

For some barbarians, the primal need to tear into their opponent barehanded is so overwhelming that wielding a weapon is a betrayal of their savage principles.  You learn arts for combat from before the dawn of sticks and stones.  Your goal is to latch on and make your prey pay for ever enraging you.  Your skills to hand on and punish your opponent will put a giant snapping turtle to shame.  Your whole body becomes a weapon, your hands, feet and grapple cause magical damage with increasing ferocity.   

Battle Hardened Frenzy

While Raging, you have resistance to all damage except psychic damage. The primal fury makes you tough enough to stand up to any punishment.

Mindless Rage

Beginning at 6th level, you can’t be Charmed or Frightened while raging. If you are Charmed or Frightened when you enter your rage, the effect is suspended for the Duration of the rage.

Inescapable Grab

Your vise-like grip and control over your grappled opponent is such that it becomes impossible to shake you off. Forced movement on your or your grappled foe attempts to move you and your grappled foe(s) as a unit.  
• You can make an opposed Athletics roll against the initiator of the forced movement to resist the movement on either you or your grappled foe. On failure, all of your grappled target moves with you.  If any of the characters end up on an occupied space, they are instead moved to an open space within 5 ft.
• Your extensive contact with your grappled target is so strong such that magic fails to distinguish you from clothing of the grappled target. Magical teleport will transport you along
with your grappled target unless they succeed an opposed grapple check using caster's spell casting ability vs. your Athletics.

You've become a master of grapple, you're so attuned to your foes during the battle, that you no longer depend on vision, hearing, or even smell to control the contest against your foe, as long as the foe is grappled by you.  You have blindsight against your grappled foe.

Should you somehow lose the grapple, you will still need your normal sense to re-grapple your foe.

Retaliation Grab

When you are the target of a melee attack, you can use your Reaction to make a grapple attempt against the attacker. On success:
• If your attacker is within 5ft, attacker is grappled.
• If your attacker is using reach weapon, attacker is disarmed.

Fist of Fury

You gain the following benefits while you are unarmed and you aren't wearing armor.

• Level 1-4:  1d4
• Level 5-10: 1d6
• Level 11-16: 1d8
• Level 17-20: 1d10

 Furthermore, the unarmed strike and grapple damage count as magical for purpose of overcoming damage resistance and immunities.