Armor of Magma

Protective magical molten rock and magma surrounds you. You gain 5 Temporary Hit Points. If a creature hits you with a melee attack roll before the spell ends, the creature takes 5 Fire damage. The spell ends early if you have no Temporary Hit Points.

Additionally, your body becomes a natural light source.  Your entire body emits a Bright Light in a 10-foot radius and Dim Light for an additional 5 feet.

Using a Higher-Level Spell Slot. The Temporary Hit Points and the Fire damage both increase by 5 for each spell slot level above 1.