Sacrificial Devotee

Some hunger for more from their patron, sacrificing their very flesh to gain more power, patrons accept the offer of one part of their body, giving power but at a cost:

Arm: Sacrifice the Right or Left arm, it becomes marked with the symbol of your patron, you gain proficiency with the weapon you are holding, you deal additional 1d8 necrotic damage with melee attacks.

Eye: Sacrifice the Right or Left eye, it glows a color of your choice, and in a pattern/design you describe, your patron enhances your reaction speed, everything seems much slower, and easier to spot, including mannerisms giving advantage on perception and insight checks, after rolling for a reaction, you may use a charge and choose the larger roll. (6 charges)

Curse: When all charges are used, you become blind in that eye, losing the passive benefits from the eye, and gain disadvantage to checks relying on sight. Vision and charges are replenished after a long rest and cannot be recovered by any other means.

Leg: Sacrifice the Right or Left leg, it's marked with the symbol of your patron, your footwork is perfect, your speed increases by 10ft, you no longer provoke opportunity attacks

Curse: The curse eats at you, controlling you, after taking damage, roll a constitution saving throw DC16, or become frightened of the attacker as the cursed leg refuses to move toward the source of fear