Yume Koujou: Doki Doki Panic

Yume Koujou: Doki Doki Panic
Developer: Nintendo Publisher: Fuji Television Platform: Famicom Disk System Released in JP: July 10, 1987 This game has unused graphics. This game has anti-piracy features.

Doki Doki Panic (Heart-Pounding Panic) is a side-scrolling platformer developed by Nintendo in collaboration with Japanese TV network Fuji TV in order to help promote their 1987 Yume Koujou (Dream Factory) event. The game revolves around an Arabian family who must venture into a dream world inside a storybook in order to rescue their two youngest children from the evil ruler Wart.

It is better known in the west as the game that served as the basis for the international version of Super Mario Bros. 2, with many of its original elements and characters ending up being incorporated into the Mario canon through their inclusion in subsequent games.

To do: There could be some unused graphics other than the smiley face.

Unused Graphics

Inside the tileset for the desert stages is a little smiley face that isn't used anywhere in this game or the prototype and final versions of Super Mario Bros. 2. It appears to just be a placeholder.

Anti-Piracy

Using early disk copying utilities would create imperfect copies of the disk due to the header field, which says how many files are on the disk, being set to one less than what there actually is. This means that the file DUMMY-DT does not get copied to the new disk. This file changes code which would normally produce this screen when the disk is set to Side B. To see this screen, remove DUMMY-DT from Side B or set the PC to $66A2 before entering a level.

(Source: http://www.famicomdisksystem.com/disk-copy/)