Arcane Smite

The next time you make a melee weapon attack during the spell’s duration, your weapon ignites in flames of arcane magic, and the attack deals an extra 1d6 fire damage to the target and causes the target to ignite in flames. When you make a melee attack, you launch a fang of fire in a 15-foot cone. All creatures within the cone must make a dexterity saving throw against your spell casting dc + Spells level above second level. On a failed throw the target is pushed back 10 feet. Half as far on a successful throw.  

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