Elemental Strike

You brandish one weapon to be used in the spell’s casting, choosing either fire, cold or lightning damage. Until the spell ends, your attacks with this weapon deals additional damage of the type you choose based on your spellcasting ability modifier. 

This spell’s damage increases when you reach certain levels. At 5th level, attack deals an extra 1d4 damage. At 11th level The spell deals 2d6 + your spellcasting ability modifier and 17th level 3d6 + your spellcasting ability modifier.