Barbarian Primal Path

In addition to the Primal Paths offered at 3rd level, you may choose the Path of the Mountain Brawler.

Path of the Mountain Brawler

The strength of the barbarian is a legendary characteristic of this otherwise diverse population of martial warriors. However, those who undertake the legacy of the mountains and become Mountain Brawlers possess a strength beyond other barbarians, a strength to match the mountains themselves.

When a Mountain Brawler barbarian enters the battlefield he subdues his foes with arms of iron, leaving them at the mercy of his allies and at the mercy of his own brutal cunning. Bones will break, blood will pour, and heads will fly, but at the end of it all the Mountain Brawler stands strong as the hills.

Arms of Iron

Starting at 3rd level you gain proficiency in Athletics. If you already have proficiency in this skill you gain proficiency in one skill from the following: Animal Handling, Intimidation, Nature, Perception, and Survival. While you are raging you add double your proficiency bonus to checks you make in Athletics and count as if you were one size larger for the purpose of determining your carrying capacity.

Oppressing Grip

Starting at 3rd level, while you are raging and grappling a target you have resistance to all damage caused to you by that target. In addition, targets you are grappling at the end of your turn take bludgeoning damage equal to your Strength modifier.

Brawling Techniques

Starting at 6th level once per turn when you take the Attack action and are grappling a creature you may replace one of your attacks with one of the Brawling Techniques below. The target of a Brawling Technique can only be a creature you are grappling. If a technique requires a saving throw, the DC equals 8 + your proficiency bonus + your Strength modifier. Your rage does not end if you perform a brawling technique but do not otherwise attack a hostile creature or take damage before the end of your turn.

Chokehold: You tighten your grip on the target, constricting them with the iron trunks you call arms. Until the end of your next turn the target has disadvantage on Strength and Dexterity ability checks and saving throws while it is grappled by you.

Bodyslam: You lift the target into the air and slam them onto the ground, releasing your hold on them. The target takes bludgeoning damage equal to 2d6 + your Rage Damage bonus and must succeed on a Strength or Dexterity saving throw (their choice) or be knocked prone. The target is no longer grappled by you.

Hurl: You spin the target round and round before releasing them, sending them hurtling towards a point in sight no more distant than twice your strength score. Any creature in a line between you and this point must make a Dexterity saving throw or be knocked prone. Upon reaching the chosen point the target must make a Dexterity saving throw or be knocked prone. The target is no longer grappled by you.

Elemental Prowess

Starting at 10th level, your fury is such so as to rival the mountains themselves. Whenever a creature takes bludgeoning damage while it is grappled by you, as a result of a Brawling Technique, or as a result of ending your grapple, such as dropping a creature from a precipice, you can instead choose to this bludgeoning damage to be thunder damage instead.

In addition, when you enter rage you can choose to become mightier than the mountains, doubling your size in all dimensions by two and your weight by eight. Your size category increases by one - from Medium to Large for example - and your attacks deal an extra 1d4 thunder damage. As your size increases however your mental capacity diminishes, and you have disadvantage on all Wisdom and Intelligence ability checks and saving throws while this effect lasts. This effect ends when your rage ends.