The Famicom Disk System version of Super Mario Bros. also contains World 0-1 but it is a full-fledged world with complete programming.

• 0-1 is a differently-textured version of 1-3, though it takes place underwater (even though there is no visible water and features bizarre elements, such as floating Princess Toadstools and floating, headless Bowsers).

• 0-2 is a carbon copy of 7-3.

• 0-3 is a copy of 4-4 that lacks its False Bowser and maze-like elements, features a different color palate (i.e. blue lava), and floating bloopers that can be stomped for 1000 points.

After beating 0-3, the player is taken back to the title screen (with the activation of hard mode upon starting the game), as if they had beaten the game.