Path of the Blood Reaper

When you take this path at level 3 you gain the ability to enter a blood rage. While blood raging you deal additional damage once per turn to any enemy within 10 feet of you. This damage scales off of the Hit Points you have lost and is equal to 1/4 of your missing Hit Points rounded down (i.e with 20 missing hit points you will deal 5 additional damage). At the end of your rage you suffer a wave of lethargy and cannot move or take any actions for one turn.

Blood of Retribution

While raging, you gain a bonus to the damage you deal on your first attack each round on any enemy within 10 feet of you. This damage equals 1/4 of your missing Hit Points (i.e if you have 20 Hit Points missing you will deal an extra 5 damage on your first attack each turn).

Throw Caution to the Wind

Beginning at 6th level, you  learn how to draw additional power from your body when  you are wounded. As an action on your turn you can boost your Strength Score by 4 points for 1 minute as long as you are not at max Hit Points. At the end of the minute you lose half of your Hit Points. If this would drop you to zero you fall unconscious at the end of the minute. Normal rules for death saving throws and death conditions still apply. Once used you must take a long rest to regain expended uses.

Frightful Blow

When you hit a creature you can use your bonus action to attempt a Charisma (intimidation) check. On a success the creature is now frightened of you until the end of your next turn. You can choose to use your action on following turns to prolong this effect. If the creature succeeds on the check it is not afraid of you and cannot be frightened by you for 24 hours.

You gain proficiency in the Intimidation skill. If you are already proficient in this skill you can double your proficiency bonus with it.

Last Resort

As a last ditch effort you throw everything you have into one blow. As an action you can make an attack that deals additional damage equal to half of your missing Hit Points (i.e if your HP maximum is 180 and you have 20 health you will deal an additional 80 points of damage) Once this action is taken you immediately fall unconscious and begin rolling Death Saving Throws. Once this ability is used you must take a long rest to recharge it.