There are a few, such as the nod to Mega Man I noted above, but they are far less obvious than other games attempting the same thing. (snackbar-games.com)
Many players feel intense emotions of sadness and loss after this point in the game; this is something many games attempt to do, but fail. (gamedesignjunkie.com)
I'd love to see more games attempt to leverage this special attribute of the medium. (gameological.com)