blood slash

you conjure a blade made of blood in a space that is 5 feet in front of you which slashes at a creature within range, releasing a wave of blood that damages nearby creatures. Make a melee spell attack against the target. On a hit, the target takes 4d10 necrotic damage. Up to 3 creatures that are within 5 feet of both you and the target make a Constitution saving throw, taking the same damage as the target on a failed save or half as much damage on a successful one.

Using a Higher-Level Spell Slot. The damage increases by 1d10 for each spell slot level above 2.