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Randomizer for Metal Gear 1 objects

This program patches the Metal Gear ROM to shuffle all the objects around, and changes which cards open which doors. It makes sure that all objects can still be found, and thus the game is finishable. It should be impossible to soft-lock the game, but this has not been extensively tested.

Public server

As a service to the community, an instance of this program runs on If you just want to try an image, you can use that.


To run, the program needs:

  • Python3
  • Python-fhs
  • Python-network
  • Python-websocketd

The three modules can be found on Without them the randomizer can still be used as a commandline program.

The modules have only been tested to work on GNU/Linux. They may not work on Windows systems.

Obviously you will also need some way to play the generated ROM image. I use the OpenMSX emulator.

Use from the commandline

If the three Python modules are not installed, running will generate an image and place it in the current directory with the name random.rom. In this mode it is not possible to change any settings.

Use as a server

If the three Python modules are installed, running will start a web server on port 9999. This can be reached by pointing your browser to http://localhost:9999/. This page will show some settings and a button to generate an image with those settings.

The settings

  • Base ROM image: There are 3 versions of the game available, and the randomizer allows to use any of them as the basis for its image. Japanese and English (Original) are the officially released games; English (alternative) is a fan translation of the Japanese rom into English.
  • Door handling: The randomizer closes all doors at the start of the game, even those that are already open in the original. When a door is opened, it may remain open or it may close behind you. Setting this to Close will mean you need to remember which card was used for which door. Setting it to Leave open means all doors will remain open, making it easier to see where you have already been. Finally Don't change will only close doors that would close in the original game.
  • Door code showing: For convenience this option will show the card which will open each door in its corner. Due to space restrictions in the ROM, this has only been implemented for the original English ROM.
  • Extreme mode: When enabled, guards don't drop items and only items which are required for reaching places are present. All other spots are empty (so there are no rations, and consumables can also be found only once).


The story is ruined by this program. Don't play the game this way unless you are familiar with the original.

What the randomizer does

In the randomizer, every area has an id. Those are shown in map.svg. Doors separate areas, as do gas chambers, breakable walls and special events such as the parachute drop. The randomizer contains information about which areas are connected and how.

First the randomizer randomly accesses areas, starting at the entry point. It stores the order in which the areas are accessed.

Then it distributes the time when the cards are found approximately evenly over that list.

It will place each card in the last room that was opened with a card before it is needed. Every new door is opened using the last card that is supposed to be found. When something other than a card is required to access an area (for example explosives to blow up a wall), those are similarly made available.

When all that is done, the items that have not been required are randomly placed on the map (unless extreme mode is enabled). After that, the remaining item spots are filled with consumables (unless extreme mode is enabled).

The items that drop when punching guards are also random consumables (unless extreme mode is enabled).


Please send any comments to, or tweet to @MakerWijnen.

Enjoy this randomizer, or if it's not your thing, ignore it and do something that you do like.


Randomizer for Metal Gear objects






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