thanks for 50 subscibers guys also the lore is that Bronze's boss let Bronze take a small leave from work just for this marble race music is listed throughout the video (when a song starts, its name and author are shown briefely)
around 14:30, you can see a marble stuck in the gate at the top of the video; i do not know which marble that it, and i apologize about that Edit: you can see them more at 16:30