The Shadow People of Hell Valley is a title bestowed to a sky texture in Super Mario Galaxy. At the beginning of the Shiverburn Galaxy level, odd shadowy figures can be seen at the top of the cliff in the background.
The official name for the image in the game files is "HellValleySkyTree" which immediately raises some questions and possible answers.
TheoriesEditThere are a few different opinions on the existence of the Shadow People. First, since the texture file is named "HellValleySkyTree" it is possible that the figures are just alien looking trees within the level. However, blowing up the image and seeing them close up raises some doubts about this idea among players.
Another popular explaination is that the texture was left in from the beta version of the game. According to this theory, "Hell Valley" was the name of the level in the beta version, but was later renamed and the shadows were left in by accident, or on purpose. Another similar idea suggests that "Hell Valley" is the Japanese name for the Shiverburn level.
Another theory implies that the images are really just local alien beings native to the galaxy watching Mario's progress from afar.