Ember Eyes

When a creature makes an attack roll you may use your reaction to send forth a burst of fire to the creature who made the attack. The target must then make a Dexterity saving throw or takes an immediate 2d8 fire damage and is set on fire. Until the creature takes an action to douse the flame they continue to take 1d6 fire damage at the start of each of their turns, half as much on a success and they are not set ablaze.

At every 2nd level above it's requirement to cast, the creature takes an additional 1d8 fire damage when initially hit with the spell.