Super Mario Bros. (NES): Tricks, Glitches, and Warp Zones

Assuming you mean the classic NES Super Mario Bros.—there are no traditional cheat codes, but several well-known tricks and glitches exist:

Useful Tricks

• Warp Zones: Specific actions in World 1-2, 4-2 access later worlds (instructions widely available online).
• Power-Up Retention: Grabbing a Mushroom/Fire Flower near level end and touching the flagpole quickly carries it to the next level.
• Wall Jumping: Precise wall jumps grant extra height for secrets/skips.
• Goomba Manipulation: Bounce on Goombas to redirect them into enemies/obstacles.

Glitches (Not Recommended)

• Infinite Lives Glitch: Exploits code bug; can cause crashes/instability.

Note: These are exploits, often frowned upon in competitive play. They're for exploration beyond intended gameplay. The most rewarding experience is playing fairly.