Is Gamzee responsible partly for the creation of Bec Noir and the slaughter of all the dream selves? He did haunt Johns dream and put Harlequins in em and John drew em out and his Dad thought he like them so he bought the one John prototyped. sooooo

Yes.  If Gamzee didn’t chucklevoodoo John then he wouldn’t have draw harlequins on his wall and is dad wouldn’t have thought he liked them and bought him the harlequin doll and if the harlequin doll wasn’t bought it wouldn’t have been prototyped and if it wasn’t prototyped the Black Queen wouldn’t have made Jack wear the clown hate and Jack wouldn’t have killed her and obtained the ring.