It's a new format! It's the human voice! Like, an original recording of your own voice, or, like, maybe another human being that you know? Sorry, don't want to come off as an ableist here; I know some people can't speak... but if you can speak then maybe you can try singing if you've never tried it ever before in your life up until now... The new format itself only requires the human voice to be featured, but this is an A Capella battle so your entry must include human voice and only human voice! :D