Path of the Thorny Guardian

Barbarians who take up the Thorny Guardian subclass channel their rage into becoming a living wall of thorns, protecting their allies and punishing their enemies who dare to get too close. They embrace the power of nature and use it to their advantage in battle, drawing strength from the thorny plants of the forest.

Thorn

As you channel the power of thorns and brambles to protect yourself. Starting at 3'rd level when you are hit with a melee weapon or melee spell attack, you can use your reaction to make spikes grow out of your skin and impale your attacker, dealing piercing damage equal to your Barbarian level plus your Constitution modifier and summon a wall of thorns around you, granting you half cover until the start of your next turn. A creature takes 1 point of piercing damage from targeting you with a melee attack while your wall of thorns is up. You can use this feature a number of times equal to your proficiency bonus per short or long rest.

Bramble Hurl

Starting at 6th level, you can use your action to command a tree or another medium or larger size plant and hurl it at your enemies. The target takes bludgeoning damage equal to 2d10 plus your Strength modifier plus 1d10 for each size the plant is above medium, and they must make a Strength saving throw (DC equal to 8 + your proficiency bonus + your Strength modifier) or be knocked prone and shoved 10 feet in a straight line. If the target is a creature that is less than one size larger than the plant you hurled, you can also create difficult terrain in a 5-foot radius around the point where the object lands. The plant has to be within 30 feet and the target has to be within 60 feet of the plant you hurl.

You can use use this ability once per long rest. Any use above that per long rest gives you one level of exhaustion.

Strength of Thorns

Beginning at 10th level, you become as tough as the plants you embody. Your AC becomes 16 + your Constitution modifier. Additionally your hardened exterior makes you tougher than other barbarians, you gain permanent resistance to piercing and slashing damage, and when you rage you gain immunity to piercing damage.

Commanding Nature

Starting at 14th level, when you hit a creature with a melee attack you can cause spikes and thorns to fully entangle the creature. The creature takes additional piercing damage equal to you Constitution modifier. It takes this damage at the start of each of it turns. The target must succeed on a Strength Saving Throw the DC is equal  8 + Constitution modifier + proficiency bonus.

• It the target success with more 5 nothing happens.
• If the creature succeeds with 5 or less it is grappled the target takes 1d6 piercing damage whenever it tries to break free of the grapple. The DC of the grapple is equal to the DC of the saving throw. 
• If it fails with less than 5 it is restrained and silenced. Any attempts by the creature to speak will cause it to take damage equal to 2d4 piercing damage and any attempt to move will deal 2d6 piercing damage.
• If the creature fails with 5 or more it is restrained, silenced and being choked. Any attempts by the creature to speak will cause it to take damage equal 4d4 piercing damage and any attempts to move will cause it to take damage equal to 4d6 piercing damage.

If the creature is grappled or restrained by this feature, you can use your bonus action to drag it 30 ft across the ground taking 1d4 slashing damage for every 5 ft it is dragged. The creature can take an action to attempt to reroll the saving throw, but gains a -1 to the roll for every time the creature fails. Is the creature failed the saving it suffers or gain on disadvantages for failing again.

You can use this feature once per short rest