メダロットnavi (GBA, 2001) is the Medarot/Medabots strategy game that never left Japan. It shipped as two cartridges the same day, Kuwagata and Kabuto, and until now it only spoke Japanese.
This project is a full translation toolkit for it: point it at your own dump, type your text, and it builds you a patched ROM. Adding a language takes a folder, not code. It ships with complete first-pass translations into English (following the Nelvana dub: Medabot, Medafighter, Robattle, Metabee...) and Latin American Spanish (following the Etcétera Group / Fox Kids dub).
https://github.com/caribbeansc/mdr-navi-i18n
Downloads: https://github.com/caribbeansc/mdr-navi-i18n/releases/latest
Medarot Navi Translation v2026.08.18
----------------------------------
Notes
------
Releases are tagged v<date>-<commit> and rebuilt automatically whenever a translation changes, so the download link above always points at the current build.
This project made heavy use of an LLM, and the current English and Spanish scripts were written entirely by one. Treat them as a starting point, not a finished localisation: 100% means every line is translated, not that every line is right.
The real value here is the tooling, ready for human translators. Every line of the game is extracted next to its Japanese, measured against the actual text box that draws it, validated and rebuilt automatically. Fixing a line is a one-minute pull request, and every correction reaches everyone on the next automatic release.
That said, the game is fully playable from start to finish in its current state.
• 100% of the game's text: all 4,480 lines across the 170 event scripts, menus, battle messages, part/medal tables and names.
• 314 graphic labels redrawn (title menu, OPTION screen, status screens, the ROBOTTLE banner...) using the game's own compressed tile formats.
• Both cartridges from the same patches: Kuwagata and Kabuto are one build with shifted data, and the tooling derives one from the other. Just pick the IPS matching your dump.
• A new Latin font (lowercase + accents) drawn into the least-used kana slots, so anything untranslated degrades to readable Japanese, never garbage.
• What the original already shows in English stays in English (ROBOTTLE!, LV/EXP, push start...).
• Tested on mGBA (every build is verified with automated in-emulator screenshot runs) and Pizza Boy GBA on Android. Reports from flashcarts and other emulators are welcome.
You need your own dump. The patches contain no game data and cannot get the game for you. Check you have the right one first:
Kuwagata (Japan) SHA-1: de8de6734f0f990832988ea133fa05241946800e
Kabuto (Japan) SHA-1: 3135545e02fa5557dda0976165cf5c7f3c0b6f8e
Grab the IPS matching your cartridge from the latest release (medarot-navi-<version>-<language>.ips) and apply it in the browser with https://www.marcrobledo.com/RomPatcher.js/, or just give the .ips the ROM's own name and keep them side by side; mGBA patches on load.
The same release ships MedarotNavi-Patcher for Windows and macOS (one universal app for Intel and Apple Silicon): point it at your dump, pick a language, click, and it writes the translated ROM next to it. It carries the repository's code and translations, never the game.
Original engine research and Kabuto translation project: https://github.com/Normmatt/Medarot-Navi-GBA-Translation
Disassembly attempt whose dual-release setup inspired one pack serving both cartridges: https://github.com/Medabots/medarot-navi
Sibling project this repository is modelled on (Medarot Card Robattle RB, Switch): https://github.com/caribbeansc/medarot-rb-i18n
Once again BIG thanks to everyone whose work made this possible.
• Normmatt & contributors - character table, script opcode sizes, the "Malias" graphics codec, already-reversed Kabuto addresses.
• The mGBA project | libmgba : https://mgba.io (all headless verification runs on it)
• RomPatcher.js by Marc Robledo : https://www.marcrobledo.com/RomPatcher.js/
This is one piece of a longer effort to translate every Medarot game. Medarot 9 (3DS) is about 60% translated, and once the series is covered, the plan is other sagas that never received a translation.
Unofficial fan project, not affiliated with Natsume, Imagineer or Nintendo. The repository and the patches contain no ROM, no graphics and no Japanese script; language packs store translations next to one-way fingerprints of the lines they replace.
This project is a full translation toolkit for it: point it at your own dump, type your text, and it builds you a patched ROM. Adding a language takes a folder, not code. It ships with complete first-pass translations into English (following the Nelvana dub: Medabot, Medafighter, Robattle, Metabee...) and Latin American Spanish (following the Etcétera Group / Fox Kids dub).
https://github.com/caribbeansc/mdr-navi-i18n
Downloads: https://github.com/caribbeansc/mdr-navi-i18n/releases/latest
mdr-navi-i18n
Medarot Navi Translation v2026.08.18
----------------------------------
Notes
------
Releases are tagged v<date>-<commit> and rebuilt automatically whenever a translation changes, so the download link above always points at the current build.
Read this first: heavy LLM usage
This project made heavy use of an LLM, and the current English and Spanish scripts were written entirely by one. Treat them as a starting point, not a finished localisation: 100% means every line is translated, not that every line is right.
The real value here is the tooling, ready for human translators. Every line of the game is extracted next to its Japanese, measured against the actual text box that draws it, validated and rebuilt automatically. Fixing a line is a one-minute pull request, and every correction reaches everyone on the next automatic release.
That said, the game is fully playable from start to finish in its current state.
What's covered
• 100% of the game's text: all 4,480 lines across the 170 event scripts, menus, battle messages, part/medal tables and names.
• 314 graphic labels redrawn (title menu, OPTION screen, status screens, the ROBOTTLE banner...) using the game's own compressed tile formats.
• Both cartridges from the same patches: Kuwagata and Kabuto are one build with shifted data, and the tooling derives one from the other. Just pick the IPS matching your dump.
• A new Latin font (lowercase + accents) drawn into the least-used kana slots, so anything untranslated degrades to readable Japanese, never garbage.
• What the original already shows in English stays in English (ROBOTTLE!, LV/EXP, push start...).
• Tested on mGBA (every build is verified with automated in-emulator screenshot runs) and Pizza Boy GBA on Android. Reports from flashcarts and other emulators are welcome.
Start Here
You need your own dump. The patches contain no game data and cannot get the game for you. Check you have the right one first:
Kuwagata (Japan) SHA-1: de8de6734f0f990832988ea133fa05241946800e
Kabuto (Japan) SHA-1: 3135545e02fa5557dda0976165cf5c7f3c0b6f8e
Patch
Grab the IPS matching your cartridge from the latest release (medarot-navi-<version>-<language>.ips) and apply it in the browser with https://www.marcrobledo.com/RomPatcher.js/, or just give the .ips the ROM's own name and keep them side by side; mGBA patches on load.
Or skip the patch files entirely
The same release ships MedarotNavi-Patcher for Windows and macOS (one universal app for Intel and Apple Silicon): point it at your dump, pick a language, click, and it writes the translated ROM next to it. It carries the repository's code and translations, never the game.
Credits
Original engine research and Kabuto translation project: https://github.com/Normmatt/Medarot-Navi-GBA-Translation
Disassembly attempt whose dual-release setup inspired one pack serving both cartridges: https://github.com/Medabots/medarot-navi
Sibling project this repository is modelled on (Medarot Card Robattle RB, Switch): https://github.com/caribbeansc/medarot-rb-i18n
Once again BIG thanks to everyone whose work made this possible.
Hacking
• Normmatt & contributors - character table, script opcode sizes, the "Malias" graphics codec, already-reversed Kabuto addresses.
Tools
• The mGBA project | libmgba : https://mgba.io (all headless verification runs on it)
• RomPatcher.js by Marc Robledo : https://www.marcrobledo.com/RomPatcher.js/
The rest of the series
This is one piece of a longer effort to translate every Medarot game. Medarot 9 (3DS) is about 60% translated, and once the series is covered, the plan is other sagas that never received a translation.
Unofficial fan project, not affiliated with Natsume, Imagineer or Nintendo. The repository and the patches contain no ROM, no graphics and no Japanese script; language packs store translations next to one-way fingerprints of the lines they replace.
Last edited by caribbeangamedev,
