Doom Blade

You brandish the weapon used in the spell’s casting and make a melee attack with it against one creature within range of the weapon. On a hit, you create a void within the weapon that cuts through the fabric of reality itself dealing 2d10 Necrotic damage. A creature hit by Doom Blade cannot heal until the start of the target's next turn and if the target is reduced to 10 hit points or less after damage is resolved, the creature dies.

This spell's damage increases when you reach certain levels. At 5th level, it deals an additional 2d10 for a total 4d10. Damage increases to a total of 6d10 at 11th level, and a total of 10d10 at 17th level and the creature dies if it is at 30 hit points or less after damage is resolved.