Exacerbate

When you see a creature take piercing or slashing damage, you can curse the wound, causing it to bleed out.  The creature must succeed on a Constitution saving throw, or take 2d4 necrotic damage at the beginning of each of its turns for the spell's duration.  The creature can attempt this saving throw again at the end of each of its turns.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d4 for each spell slot above 1st.