Consuming Blade

You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within range of that weapon. On a hit, the target suffers the weapon attack’s normal effects and is then surrounded by deathly energy until the start of your next turn. If the target deals damage to you before then, the target takes 1d4 necrotic damage and the spell ends.

At Higher Levels. At 5th level, the melee attack deals an extra 1d4 necrotic damage to the target on a hit, and the damage the target takes when it deals damage to you increases to 2d4. Both damage rolls increase by 1d4 at 11th level (2d4 and 3d4) and again at 17th level (3d4 and 4d4).