using supernal surge, the way i read it, you can attack with your action as well as a BA and then become spectral, or do you need to use a bonus action to activate the feature? as well once you get the feat can you always attack with BA or only when your spectraThe feature can trigger when you Attack (and thus get a BA attack) and then you are spectral, or you can just use your BA to become spectral without needing an attack (if you wanted to move spectrally first)

— Matthew Mercer (@matthewmercer) December 27, 2017

You can only attack as a BA for that turn, and only for as many uses of the ability as you have.

— Matthew Mercer (@matthewmercer) December 27, 2017