Hey! I am glad you enjoyed the game! Regarding the Attacking mechanic, you first need to transform and right click when facing the skull; the attacking mechanic was pretty much added in last minutes so it might be a bit buggy and unresponsive which i do plan on fixing post jam.
And you are right; the theme of duality was in reference to the transformation, it was inspired by the story of jekyll and hyde. I planned to provide a bit more exposition in the opening cutscene however i couldnt due to time constraints! (which again would be fixed post jam.)
PS the vocals were synthesized using SAM (software automatic mouth) which is a fun piece of software to play with in its own right!