Blade of the depths

When hitting a creature with a weapon attack during this spell, the weapon emits a devilish gleam as you strike. The attack deals a base of 1d6 slashing, 2d6 necrotic and 1d6 fire damage to the target which becomes visible if it is invisible, and the target sheds dim light in a 5-foot radius and can’t become invisible until the burning condition ends. The target takes 2d4 burning damage per turn, for the next 3 turns.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the extra damage increases by 1d6 for each slot level above 2nd.