Voodoo Doll

Choose a Creature you can see, you make a small effigy of them, they make a Charisma Saving Throw, on a fail the effigy takes on some of their very life essence. The Doll has an amount of HP equal to your Maximum HP, and each time you would take damage the effigy takes half of the damage instead of you, or you can use your Reaction when you would take Damage to force the effigy to take all the Damage. Any damage the effigy takes, the creature the effigy is made of takes the damage too as Necrotic Damage. If the effigy reaches 0 HP it is destroyed.