Deeply curious: some enemies in the final stage seem to appear there and nowhere else (Ra, Alpha, Beta, Sigma, Darwinite, Ghost, Falcon, and probably others). There are gaps in the album which I imagine are meant for these characters. Was this an intentional feature?
 "Clicker Party"){kind=icon}
 "The Enchanted Cave"){kind=icon}
 "Escape from the Video Shop"){kind=icon}