Valkyrie Strike

A fountain of flame and light form spectral wings upon your back and alight your weapons with radiant energy. For the duration you shed 20ft of bright light and 20 ft of dim light, your movement speed is increased by 30ft, your gain a fly speed equal to your movement speed, and you do not provoke attacks of opportunity. In addition while in this form you deal an extra 2d8 radiant damage when you hit with a weapon attack. As an action you can end the spell with a fiery explosion, each creature of your choice within 20ft of you must make a constitution save or take 3d8 radiant and 3d8 fire damage or half as much on a success