
Super Mario Bros 3 Mix
About the Game
Super Mario Bros. 3Mix is a large-scale NES game of 3 created by Captain Southbird (Southbird). It keeps the basic SMB3 engine and presentation while incorporating ideas, mechanics, characters, level themes and music from many other Mario games. The completed Rev 2B version was released in 2015.
๐ A Much Larger Version of SMB3
Super Mario Bros. 3Mix goes well beyond a normal level hack.
You get:
- New levels.
- Remixed SMB3 levels.
- New enemies.
- New bosses.
- New power-ups.
- Star Coins.
- Alternate exits.
- Save functionality.
- Re-entry into previously completed worlds and levels.
- Character selection.
- New music from other Mario games.
- World-specific gameplay mechanics.
The project was designed as a tribute to the broader Mario series. Southbird explained that the original idea was to take concepts from later Mario games and see how they could work inside the SMB3 framework.
๐ฎ The NES Game Engine Gets New Tricks
The original Super Mario Bros. 3 engine was heavily modified for 3Mix.
Some of the most notable changes are:
- Reverse-gravity sections.
- Star Coins.
- Flagpole endings.
- New switch mechanics.
- Alternate exits.
- Yoshi gameplay.
- New power-ups.
- Custom bosses.
- World-specific mechanics.
- New map functionality.
- Save files.
Southbird's own source code is publicly available, which provides unusually strong documentation for a game of this size.
โญ 300 Star Coins to Collect
Star Coins are one of the biggest additions to the game.
There are 300 Star Coins distributed throughout the adventure.
You can:
- Search levels for hidden Star Coins.
- Return to completed levels.
- Collect Star Coins that you missed.
- Use collected Star Coins to unlock additional portions of the game.
- Work toward the game's secret endgame content.
The 300-Star-Coin requirement also appears in the game's speedrunning documentation. A documented 100% completion definition requires all 300 Star Coins along with defeating Bowser and Count Bleck.
๐บ๏ธ The World Map Lets You Go Back
3Mix changes the way you revisit earlier content.
Once you have completed an area:
- You can return to previous worlds.
- Completed levels remain marked as completed.
- You can revisit levels to search for missing Star Coins.
- The Star Road menu provides access to previously visited worlds.
This system makes collecting all of the Star Coins practical without forcing you to restart the adventure.
๐จโ๐ฉโ๐ฆ Choose Mario, Luigi or Toad
The game gives you a character-selection option.
You can choose:
- Mario
- Luigi
- Toad
The characters are cosmetic choices rather than separate gameplay classes. The published feature list specifically describes the character selection as cosmetic.
The game also supports two-player play.
๐ฅ New Power-Ups
3Mix includes several power-ups that do not appear in the original SMB3.
The documented additions include:
- Penguin Suit
- Carrot / Bunny power-up
- Boomerang Suit
- Yoshi
- Classic SMB3 power-ups such as the Mushroom, Fire Flower, Star, Leaf and Hammer Suit remain available.
Penguin Suit
- Takes the place of the Frog Suit in the hack.
- Allows Mario to use ice-based attacks.
- You can freeze enemies.
- Frozen enemies can be kicked.
Carrot / Bunny power-up
- Comes from Super Mario Land 2: 6 Golden Coins.
- Gives Mario bunny ears.
- Allows him to hover or descend slowly.
- It does not provide the full flying ability of the Raccoon Suit.
Boomerang Suit
- Uses boomerangs instead of the Hammer Suit's hammers.
- It is based on the Boomerang Flower concept from later Mario games.
๐ฆ Yoshi Joins the Adventure
Yoshi is another major change from the original NES game.
The Yoshi implementation takes inspiration from Super Mario World.
You can:
- Ride Yoshi.
- Use Yoshi to attack enemies.
- Use Yoshi in specific level puzzles.
- Use Yoshi in areas designed around his abilities.
Yoshi appears in World 4, according to gameplay documentation.
๐ Gravity Can Flip
One of the most technically ambitious features is the reverse-gravity mechanic.
Certain sections can turn the normal gravity direction upside down.
This mechanic becomes especially important in World 7.
Southbird explained that implementing reverse gravity required extensive changes to the game's collision and movement logic. The idea was partly inspired by the gravity mechanics of Super Mario Galaxy.
World 7 contains several gravity-switching sections, including upside-down stages and castle areas.
๐ด New Switch Mechanics
3Mix includes several switch types.
These include:
- Switch doors
- Coin Snake switches
- ! switches
The switch mechanics borrow ideas from Super Mario World and later Mario games.
The ! switch can perform different functions depending on the level.
It can:
- Raise a pipe.
- Reveal blocks.
- Turn lights on in dark stages.
๐ป Ghost House Gameplay
Some levels use mechanics associated with later Mario ghost houses.
The game contains:
- Dark areas.
- Boos.
- Light switches.
- Ghost-house puzzles.
- Areas where darkness affects how you progress.
In some dark sections, activating the light can stop the Boos from constantly chasing you. Gameplay documentation confirms this mechanic in later levels.
๐ Worlds Inspired by Different Mario Games
One of 3Mix's defining ideas is that different worlds pay homage to different Mario games.
The documented longplay shows:
| World | Main Theme |
|---|---|
| World 0 | Super Paper Mario / Southbird's childhood level concepts |
| World 1 | Super Mario Bros. |
| World 2 | Super Mario Bros. 2 |
| World 3 | Luigi's Mansion |
| World 4 | Super Mario World |
| World 5 | Super Mario Land |
| World 6 | Super Mario Sunshine |
| World 7 | Super Mario Galaxy |
| World 8 | Various Mario games |
The longplay identifies these themes directly in its chapter structure, while Southbird explained the design philosophy behind several worlds in interviews.
๐ฐ World 0 Is a Secret Bonus World
World 0 is not simply another standard world.
Southbird described it as a bonus world that becomes available after collecting the required Star Coins. It also appears earlier through secret exits in certain worlds.
Its design has a personal connection to the creator.
According to Southbird:
- Some core World 0 levels originated from his childhood drawings.
- The world uses a theme inspired by Super Paper Mario's Castle Bleck.
- Its appearance is intentionally darker than the main worlds.
RetroAchievements also confirms World 0 as a separate playable world with its own Star Coins.
๐น New Bosses
3Mix does not simply reuse the original SMB3 boss encounters.
The hack contains:
- New bosses.
- Bosses inspired by other Mario games.
- Remixed boss concepts.
- World-specific boss encounters.
The final World 8 sequence eventually leads to Bowser's Castle and a battle with Bowser.
๐ต Music From Across the Mario Series
The soundtrack also follows the game's tribute concept.
You will hear:
- Classic SMB3 music.
- Music borrowed or adapted from other Mario games.
- New music arrangements.
- Music associated with specific world themes.
Southbird explained that NES audio limitations made music one of the technically difficult areas of the project, so MIDI files were carefully adapted for the hardware.
๐พ Save Your Progress
Saving is a major quality-of-life change.
Unlike the original NES release of Super Mario Bros. 3, 3Mix provides:
- Three save files.
- Save functionality during the adventure.
- Persistent level-completion information.
- Ability to return to previously completed worlds and levels.
This is particularly useful because the game contains hundreds of collectibles.
๐ The Mushroom House Game Is Different
The traditional SMB3 card-matching system receives a major change.
The game uses a memory-card-style game inspired by later Mario titles.
The documented version allows you to continue selecting cards until you encounter two Bowser cards. The prizes you obtain are retained.
๐ฉ Flagpole Endings
The traditional SMB3 goal-card system is replaced in many parts of 3Mix with flagpole endings.
Southbird explained that the flagpole was introduced partly because Star Coins required persistent collection tracking.
The hack therefore uses a familiar goal from the later 2D Mario games while retaining the SMB3 engine.
โ๏ธ Prankster Comets
3Mix also contains Prankster Comets.
These provide additional challenges after or alongside the main level progression.
Documented examples include challenges based around:
- Collecting coins.
- Completing levels while small.
- Other modified conditions.
They provide another way to replay sections after you have already completed their normal objectives.
๐ Alternate Exits
Some stages contain alternate exits.
Finding one can:
- Open another route.
- Reveal additional areas.
- Help unlock parts of the game's progression.
- Provide access to hidden content.
This makes exploration important beyond simply reaching the normal flagpole.
๐ฎ How to Play
Super Mario Bros. 3Mix is an NES/Famicom game, based on the USA version of 3. The final Rev 2B patch supports both the PRG0 and PRG1 USA ROM variants.
| NES Button | Keyboard |
|---|---|
| D-Pad Up | Arrow Up |
| D-Pad Down | Arrow Down |
| D-Pad Left | Arrow Left |
| D-Pad Right | Arrow Right |
| A | Z |
| B | X |
| Start | Enter |
| Select | V |
Basic controls
- Arrow Keys: Move Mario, Luigi or Toad.
- Z: Jump / confirm.
- X: Run, use power-up abilities or perform the secondary action.
- Enter: Start / pause.
- V: Select.
Two-player mode
- The hack supports two-player gameplay.
- You can select Mario, Luigi or Toad.
- Character selection is cosmetic rather than a different ability system.
๐ฑ Mobile Controls
If you run the NES ROM through EmulatorJS on mobile:
- Use the virtual D-pad for movement.
- Use the virtual A button for jumping.
- Use the virtual B button for running and other secondary actions.
- Use Start for menu functions.
- Use Select where required.









































