SKBN (Master System game)

SKBN is an implementation of the classic puzzle game where you must move boxes to specific locations within a maze. Compatible with PAL and NTSC 50 pin (export/non-Japanese) Master System consoles, or Japanese SMS/Mark-III using a separate adapter.

  •  The game cartridge
  •  The game cartridge
  •  The game cartridge
  •  Title screen
  •  Level collections
  •  The "Ksoko" theme
  •  The "Mac" theme
  •  Level preview
  •  Options menu
  •  Example supported controllers
  •  Example supported controllers
  •  Example use with the Mega Mouse


This is a physical edition of the SKBN homebrew game for the Sega Master System.

  • A total of 1736 built-in puzzles of all difficulty levels.[1]
  • 4 themes to choose from (V2, V1, Mac and KSoko)
  • Optional point mode (Simply point where to go using the controller and the game finds the shortest path)
  • Compatible with PAL and NTSC consoles (50 pin / non-Japanese)
  • Also works on Japanese SMS consoles and Mark III using an adapter
  • Compatible with the power base converter (or equivalents)
  • Supports SMS Control pads, the Sports Pad, Megadrive controllers[2] and the Mega Mouse.[2]
  • Memory type: Flash
  • Save RAM: None. Completed puzzles and options are stored in Flash. No battery!
  • Current version: 2.0

The game is sold as "cartridge only", without box nor manual. There is no sticker on the back of the cartridge, and there is a small slot on the top which serves absolutely no purpose (see pictures).

Built using our 4Megabit reprogrammable cartridge PCB.
For more information about this homebrew SMS game, visit the project page:

[1] Included levels used with the permission of their authors. Thanks to David W. Skinner for the Microban and Sasquatch collections. Thanks to Jaques Duthen for the Dimitri & Yorick, Sokogen-990602, Sokogen-990702, Sokogen-990917, and Sokogen-991123 collections.

[2] Megadrive controllers and the Mega Mouse are not supported on the Sega Mark III.


Buy here

In stock : Ships within 5 business days unless noted otherwise (out of stock, pre-order, holidays, etc).
DescriptionGame cartridge for Master System: SKBN
product picture

We normally ship within 5 days (excluding week-ends and holidays) after payment.
Prices are in US dollars and are subject to change without notice.

Compatibility list

IMPORTANT: This is not a complete list. If something does not appear here, it simply means that we did not get the chance (or the idea) to test it, or that no one let us know that it works.

Help us improve this page by sending test results by email to

Tested Controllers

Show list...
ModelTested bySupportedComments
SMS Control Pad (standard controller)raphnet.Yes
3 Button Megadrive controllerraphnet.Yes
6 Button Megadrive controllerraphnet.Yes
Sega Sports Pad (SP-500 / Japanese model)raphnet.Yes
Mega Mouse (MK-1645)raphnet.Yes
Sega Mouse (Japan/Europe model with colored buttons)-Unknown / Not testedPlease test and report!
Sega Sports Pad (larger North American version)-Unknown / Not testedPlease test and report!

Download(s) & Link(s)

Version: 2.0 - Latest

September 14, 2022
File(s) (186.7 KB)
After about a year of working part time on this project, version 2 is finally ready!
  • Added 100 raphnet levels (mostly very easy)
  • Added more levels by Jacques Duthen, previously unpublished: Sokogen-990702, Sokogen-990917, and Sokogen-991123
  • Updated the title screen
  • Added options and credits screens
  • Add themes: New (V2), Mac and Ksoko. V1 theme still available.
  • Change keys in-game: Button 1 opens the menu, Button 2 undos the last push.
  • Support for point mode (with path finding)
  • Support for the Sports Pad and the Mega Mouse
  • Add background music (can be turned off in the options)

Show previous releases...

Version: 1.4

May 21, 2021
File(s) (125.2 KB)
Correct the spelling of 'Dimitri & Yorick'

Version: 1.3

March 31, 2021
File(s) (125.2 KB)
  • Add a 'Well Done' message when solving a level
  • Fix a bug where the player could move in diagonal, and undoing the last move would then remove a wall block and add a new box to the level!
  • Move the Level number in the status bar one column to the right to avoid displaying text in the first column.
  • Small tweaks to the tile screen (sharper box corner, black countour)

Version: 1.2

March 30, 2021
File(s) (121.4 KB)
  • Added a 24x24 tiles mode.
  • Boxes now move smoothly, in-sync with the player when pushed. (instead of teleporting).
  • Reworked the player artwork and other small cosmetic details.
  • Correct a bug which caused unsolved levels to show as solved in the menu when scrolling.
  • Display 'player on target' correctly during previews.

Version: 1.1

March 29, 2021
File(s) (115.2 KB)
  • Add a short 'end level' jingle.
  • Add 'Dimitri & Yorick' and 'Sokogen-990602' level sets by Jacques Duthen (Easy levels)
  • Fixed the 'parallax' effect at the end of a level (was not well controlled and jittery on real hardware).
  • Correct initial player position (was not centered until first movement)
  • Fine tune player sprite position in 12x12 tiles levels (was a bit too low)
  • Remove the debug info (number in upper right corner) in 12x12 tile display mode

Version: 1.0

March 27, 2021
File(s) (0 B)
First release for coding competition 2021

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