Coagulate

This cantrip causes the blood of creatures around the caster to turn sludgy. All creatures in range must make a Constitution saving throw or take 1d4 points of necrotic damage and inflict half damage on their next successful melee attack before the caster's next turn. If the target saves, they take no damage and suffer no other effect.  As the casters level increases, the cantrip will do 1d4 additional damage at 5th level (2d4), 11th (3d4), and 17th (4d4).