Path of the Sanguine Surger

Barbarians who walk the Path of the Sanguine Surger care little for their own safety, and draw upon their strength to shatter as many foes as they can, at the cost of their own body. Most Barbarians who walk this path end up covered in blood through their fighting - either their own blood or the blood of others around them.

Blood Surge

Starting when you choose this path at 3rd level, you can choose to go into a Blood Surge when you rage. Whenever you choose to go into a Blood Surge, and thereafter at the start of your turn, you expend one of your hit dice - whenever you make a melee weapon attack while in a Blood Surge, you deal additional damage equal to the number rolled on the hit die for each damage roll you make during that turn.

At the start of your turn while you're in a Blood Surge, as well as when your rage ends, you take Necrotic damage equal to your character level.

Sanguine Artistry

At 3rd level, you also know how to use your own blood as a warning.

You gain proficiency with Calligrapher's Supplies if you did not have it already.  

Over the course of 1 minute, you are able to paint your body with a special blood-based paint. While your body is painted by this mixture, you gain advantage on Charisma (Intimidation) checks. The paint flakes off after 1 hour, or after spending any time being submerged in water.

Bolstering Blood

At 6th level, you can choose to end your Blood Surge early. Whenever you are in a Blood Surge, you can choose to end it early as an Action. When you do, your rage ends, and you instead regain hit points equal to the amount of damage you dealt on your previous turn instead of taking Necrotic damage. 

As well, you can choose to expend more than one hit die while you are in a Blood Surge - you are able to expend a number of hit dice equal to half your proficiency bonus (rounding up) to determine the extra damage from your Blood Surge.

Moreover, you also make Death Saving Throws with Advantage.

Veins of Endurance

At 10th level, your body has gotten so used to damage that you can shrug some of it off. As a bonus action on your turn, you can choose to expend one of your hit dice to gain resistance to all damage except Psychic damage until the start of your next turn.

As well, when you drop to 0 hit points, you can choose to drop to 1 hit point instead. Once you drop to 1 hit point in this way, you cannot do so again until you take a short rest. 

Dyed in Red

At 14th level, you have become so attuned to blood around you that you can bolster your own essence with it. Once per turn, when you make a damage roll as part of an attack while in a Blood Surge, you can choose to regain hit points equal to half the damage you deal.

As well, whenever you score a critical hit while in a Blood Surge, you can choose to expend a number of hit dice equal to your proficiency bonus as part of the attack, and deal extra damage equal to the number rolled - this damage is in addition to your Brutal Critical damage dice.