Bloodmage

You understand the hidden power within the most creatures life force. You can bend and manipulate the blood to use it for your own benefit. The pupils of the blood seeks the knowledge of how to manipulate their own and others life force and blood.

Heightened Blood

At 2nd level as an action you can magically manipulate the blood of a creature you can see within 30 feet of you.  The creature gains temporary hit points equal to half of your wizard level + intelligence modifier. You can use this feature equal to your proficiency bonus. You regain all expended uses when you finish a long rest.

Upon reaching 10th level in this class the creature gains temporary hit points equal to your wizard level + intelligence modifier.

Life Devourer

At 6th level whenever you cast a spell on a creature that allows you steal a creatures life force (Vampiric touch, Enervation etc.)  roll 2d4 you regain additional hit points equal to the number rolled.

The dice roll increases to 4d4 at 11th level and 6d4 at 14th level.

Boiling Blood

Upon reaching 10th level your understanding with blood deepens. The Life Devourer's dice pool increases to 4d4.

Additionally as a reaction whenever a creature deal damage with a melee attack within 60 feet you can expand a number of your hit die and reduce the number rolled from the damage dealt by the creature. When you do so you feel like your blood is boiling inside your body. You take necrotic damage equal to the number rolled. This damage cannot be reduced by any means.

Puppeteer of Blood

Upon reaching 14th level you master the manipulation of blood. The dice pool for Life Devourer increases to 6d4.

At 14th level as  as an action you can magically manipulate the blood of creatures of within 30 feet of you for up to 1 minute or until your concentration ends (as if you were concentrating on a spell). For the duration whenever a hostile creature enters, starts or ends its turn within 30 feet of you it must make Constitution saving throw against your spell save DC. On a failed save it takes 5d10 necrotic damage and it cannot use reaction until the end of its next turn.  On a successful save, it takes half as much damage, and can use reactions.

Once you use this feature, you can't do so again until you finish a long rest or until you expend a spell slot of 4th level or higher on it.