Cauterize

Fire burst out of you, all other creatures within 5 feet of you must succeed on a Dexterity saving throw or take 1d8 fire damage. If this damage is higher than the creatures current HP, they heal by that amount instead. You regain 4 HP.

Note: A creature may choose to fail this saving throw.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d8 for each slot level above 1st, and you heal for an additional 4 HP.