Crimson Pact

Prerequisite: Ability to cast at least one spell 
You have mastered the forbidden art of blood magic, forging raw arcane power through the sacrifice of your own life’s essence. In doing so, you replace material components with the crimson offering of your blood, bending magic to your will.

When casting a spell, you may choose to ignore its material components, even if they have a listed gold piece cost or are consumed by the spell.
You take necrotic damage equal to 5 × the spell’s level.
If the spell has a material component worth 500 gp or more, you must succeed on a Constitution saving throw or gain 1 level of exhaustion.

The saving throw DC is calculated as follows:
For components costing between 500 gp and 1,000 gp, the DC is 12.
For components costing more than 1,000 gp, the DC increases by 1 for every additional 500 gp above 1,000 gp.

 Feat Greater Crimson Pact (10th Level)
Prerequisite The ability to cast at least one spell And Crimson Pact

You learn to channel your blood magic through a cantrip called Blood Leach. As a bonus action, you can cast Blood Leach, making a spell attack against a creature within 80 feet. On a hit, blood oozes from their eyes nostrils, Cuts and gashes dealing necrotic damage equal to 2d4 + 1d4 for every two spell levels beyond 1st (minimum 2d4 damage). You can then cast your next spell without paying its material components 

Casting Time: Bonus Action

Range: 80 feet

Components: V, S
Duration: Instant bonus action
Attack: Spell Attack (melee or ranged) Immune to any creature That is immune to bleed damage
damage 2D4 Necrotic Damage + 1d4 for every two levels After that
on hit your next spell Does not require material components
On hit the target must make the Constitution saving throw associated with the material component cost for your next spell. On a failed save, the target gains 1 level of exhaustion instead of you.

Effect:
your fingertips glow with a deep crimson light, as if blood itself fuels the arcane energies. The air around you thickens with power drawn directly from your life force, binding your magic to thare own vitality. When you strike with Blood Leach, blood seeps from your foe’s eyes, nostrils, and Wounds their life essence feeding your arcane power.