Counting yourself at home in the company of the seediest taverns, the most brutal fighting pits, and walking the most dangerous streets when others wouldn't dare.  You welcome the threat of death as though it were an adrenaline rush that makes you feel alive.  Wherever you go, no one knows your name, rather they refer to you with simple terms:  Brute, Bruiser, Brawler are the most common and few become very familiar with your presence many would rather keep their distance.  You make your living by contests of strength and vigor, occasionally the enterprise of fisticuffs for the highest bidders.

Bruiser

The Brute is a master of intimidation and is especially deadly with the bludgeoning weapons that some might call his hands. Once these weapons are closed and ready for a brawl there is little that remains standing in the Brute's way. Choosing this subclass at the third level grants the barbarian the Bruiser feature adding proficiency of unarmed strikes. At this level, these strikes deal bludgeoning damage of 1d4 + the barbarian's strength modifier.

The bruiser feature increases to a 1d6 at level 5.  Additionally, at levels 11 and 17, the bruiser damage die increases by an additional 1d6.  

Also at level 3, You gain expertise with intimidation skill.

A Mean Right Hook

As a reaction to an opponent that misses an attack against him, the Brute can take the opportunity for himself to make a bruiser strike against the opponent. Taken off guard, the opponent is forced to succeed a Constitution saving throw or be stunned until the start of the brute's next turn; The DC for this save equals 10 or half the damage you take, whichever number is higher.

The brute's unarmed strikes are now considered magical for overcoming resistance.

Shake it Off

As the Brute gains their 10th level, their ability to keep the fight going well beyond the normal means of most beings' ability to resist pain and stay standing.  The Brute now gains the Shake it off feature, as a number of times equal to the barbarian's Constitution modifier per long rest the Brute can add their constitution modifier to their Armor Class or a Strength, Dexterity, or Constitution saving throw to avoid damage.  Any attack that requires the barbarian to take half damage on a successful save, the barbarian now takes no damage.

Adrenaline Rush

Upon reaching the 14th level, the Brute's ability to deliver punishment and resist pain becomes unparalleled to that of many mortal creatures.  A number of times equal to the Brute's Constitution modifier per long rest, when the Brute enters a rage he gains a number of temporary hit points equal to his barbarian level.