Sanguine Fury

The blood of others empowers your own tainted blood, allowing for more lethal spellcasting at the cost of your own vitality. 

As a bonus action, you can drink a vial of a creature's blood. Doing so allows you to add your charisma modifier to any damaging spell you cast for 1 minute. During this time, you also have advantage on strength and constitution-based skill checks and saving throws, and you gain a number of temporary HP equal to twice your sorcerer level. Once the minute is over, you suffer one level of exhaustion and lose any remaining temporary HP. 

You can perform this ritual a number of times equal to your proficiency bonus, which resets every day at dawn.