Channelling the chill fo the grave, make a melee spell attack against a target within reach.
On a hit, the target takes 1d10 Necrotic damage, and it can't regain HP until the end of your next turn.
At Higher Levels: The damage increases by 1d10 when you reach levels 5 (2d10), 11 (3d10),and 17 (4d10)