D&D Next: Balefire--Cantrip for Arcane Magic-Users

Balefire 
(Cantrip on the Wizard's Spell List)

Effect: Make a magic attack against one creature within 80 feet of you. On a hit, the target takes 1d6 fire damage.  If a 6 is rolled, roll another die and add it to your total, continue to do this until you no longer roll a 6.
Special: If your caster level is 7th or higher, the damage is 3d6. If your caster level is 11th or higher, the damage is 4d6. If your caster level is 16th or higher, the damage is 5d6.