Blood Marauder

With blood magic banned throughout the lands of Xvendreth by the Court of the Magi, many have learned to practice blood magic in secret. Due to no formal training in blood magic, the practice of blood magic has been twisted over its many years of use in Xvendreth. Practioners of blood magic often suffer corrosive properties in their blood when frequently using their blood magic. 

The Blood Marauder uses blood magic in conjunction with traditional weapons in order to allow themselves to recuperate from use of their blood magic without leaving themselves vulnerable to attack. Their blood magic specializes in overtaking foes while allowing them to close the distance to the next target on their list. As they continue to use their potent blood magic, they begin to endanger their own health in the process and must consider their choice carefully each time they use their blood magic. 

Caustic Blood

Starting at 3rd level, you gain the ability to access powerful blood magic. Improper use of the power of blood magic builds up bile and corruption within you, enhancing your martial prowess. However, you have a limit. Each use of your forbidden magic builds varying amounts of causticity in your blood based on how much power it takes to access the ability. Therefore, the stronger the ability, the more caustic your blood will become. At 100 causticity, your body becomes overwhelmed and immediately begins to die, causing you to make death saving throws regardless of hit points remaining when 100 causticity was reached. Each round you does not gain causticity, you begin to lose causticity at the start of your next turn, losing 10 causticity every round after a full round of not gaining causticity.  While you have causticity, enemies take damage as a penalty for injuring you, taking a d4 damage if your causticity is within 1-30, d6 for 31-60, and d8 for 61-99.

You gains the following abilities:
Bite of Dread: You can influence an opponent to feel dread using a standard action to cause them to have disadvantage on all saving throws. Your target makes a wisdom saving throw (DC = 8 + Proficiency Bonus + Charisma Modifier). You gain +10 causticity per use and the effect holds for 3 rounds if the target fails the saving throw. The target can attempt to save again at the beginning of its next turn, and once cleared of Bite of Dread, the target cannot be affected again for 24 hours.

Splash of Blood: You use your standard action to draw upon the River of Blood and sends a splash of blood upon your enemy that seems to manifest from nowhere. The target makes an Intelligence Saving Throw (DC = 8 + Proficiency Bonus + Charisma Modifier), and upon failure, falls under the effect of Feeblemind [as per the spell] for 3 rounds. The target can attempt to save again at the beginning of its next turn, and once cleared of Splash of Blood, the target cannot be affected again for 24 hours. You gain +10 causticity per use.

Seep the Blood: You drain the blood from nearby, recently-slain foes. Upon reducing a creature to 0 hit points, you may use your bonus action to gain temporary hit points for 3 rounds equal to half the damage dealt by the killing blow. You gain +10 causticity per use. If this effect is invoked while Seep the Blood is already active, the new cast replaces the old cast of Seep the Blood and the effect does not stack.

Reach From Below

At 7th level, you reach into the ground below using your potent blood magic as a bonus action. A target of your choice within 30 ft of you must succeed a Dexterity saving throw (DC = 8 + Proficiency bonus + Charisma modifier) or a hand of blood pulls the target 15 ft towards you along the straightest line. Usable a number of times per long rest equal to your charisma modifier (minimum of 1.) If the target succeeds the saving throw, they have advantage on their first attack against you on their next turn. If the target is aware of the your action and willing to be targeted by you, no dexterity save is required.  You gain +20 causticity per usage.

Blood Shield

At 10th level, when an enemy you see attacks you, you may use your reaction to avoid the damage by stepping through a Blood Rift.  You gain +40 causticity per use. You may use this feature a number of times per long rest equal to your Charisma modifier (minimum of 1).  You may use this ability on a friendly target, however, half the damage that would've been taken is transferred to you.

Blessed by Blood

At 15th level, you use a standard action to coat your weapon in the blood of warriors long past. On your next strike with that weapon within 5 rounds, the weapon deals Xd6 bonus damage where X is equal to your charisma modifier. This can be used once per long rest. You gain +30 causticity per use. X decreases by 1 for each round that the weapon remains unused after the first round. (cannot be reduced beyond 1d6)

Blind with Blood

At 18th level, you may use a standard action and choose a foe to bind in a blood pact to the death. The target must succeed a Wisdom saving throw (DC = 8 + Proficiency bonus + Charisma modifier.) If the target fails the saving throw, for 10 rounds, that opponent sees dim light within 10 feet of himself and darkness beyond that. This effect has no affect on creatures that possess blindsight, but does count as magical for the purpose of overcoming obstruction to vision. This darkness cannot be overcome without a spell. This darkness follows the target until the effect ends. You gain +30 causticity per use.