New Super Mario Bros. Cheats

Challenge Mode
In save files where you've beaten World 8, you can try NSMB's Challenge mode, which doesn't let you scroll to the left or downward, depending on the stage. Turn on Challenge mode by pressing Start on the map screen, followed by L R L R X X Y Y. When you enter the code, a message welcoming you to Challenge mode will appear, along with an arrow icon in the upper-right corner of the map screen. A red arrow icon means that the stage will have scrolling limitations. For unbeaten stages, auto-scrolling stages, and a few others, the arrow icon will be gray, which means that they won't be affected by Challenge mode. If you get stuck and can't remember what the welcome message told you, don't move for 40 game seconds and another message will appear to remind you that you can press Start and choose "Return to map" to leave the stage. Back on the map screen, you can turn off Challenge mode with the same code.