Hi Zero! As long as you have a Mic (built-in or otherwise) that Unity can discover, you should be able to play. Are you seeing the "Plug in a mic" screen despite having a built-in one?
yup!! my computer should have a built-in one but it still pops up ><
We don't have a solution for you right now, but we're looking into it! Thanks for letting us know.
Yw!! Ty for making such an intresting concept and a cool game!! ^u^