Pokémon Odyssey
Play Pokémon Odyssey
A free Pokémon Fire Red ROM hack. Get playing in 3 simple steps below — everything happens right here in your browser — nothing you pick ever leaves your device.
What You’ll Need
New to ROM hacks? Here’s the simple version — three things come together to make Pokémon Odyssey, and we take care of two of them for you.
Your Own Fire Red Game
A legally-owned copy of Pokémon Fire Red. This site does not provide this part — you will need to already have it before you start.
The Odyssey Patch
The free file that turns Fire Red into Pokémon Odyssey. Our tool below applies it for you automatically — no technical steps required.
Setup Help
An emulator is free software that plays your patched game file on a computer, phone, or handheld device. See “Which emulator should I use?” in the FAQ below for the full list.
Already have your Fire Red file ready? Skip straight to the tool ↓
Download the Files
These are the official Pokémon Odyssey files, released directly by the development team — not a fan mirror or third-party upload. Two versions are available. Both are ZIP files holding a small patch (not the full game) plus setup docs — everything is under 5 MB.
v4.1.1
ZIP file · ~4.5 MB
- Patch file: Odyssey.ups
- Patch Notes.txt — what changed in this version
- HOW TO PLAY.txt — setup instructions
- Documentation folder — guide links (level caps, stats, teambuilding, wild encounters)
v4.0.3
ZIP file · ~4.5 MB
- Patch file: Pokemon Odyssey.ups
- HOW TO PLAY.txt — setup instructions
- Documentation folder — guide links (level caps, stats, teambuilding, wild encounters)
Unzipping the file
- Windows: right-click the downloaded ZIP and choose “Extract All.”
- Mac: double-click the ZIP to extract it automatically.
- Open the extracted folder — the .ups patch file inside is what you’ll upload to the tool below (or to Rom Patcher JS if patching manually).
What’s New in v4.1.1
- Fixed a battle-team swap issue with Olympia
- Fixed Triple Axel’s damage scaling
- Fixed F.O.E. respawning at the Guild
- Added Fake Out to Politoed’s learnset
- Added Weather Ball to Roserade’s learnset
- Buffed Iron Tail’s accuracy from 75% to 85%
- Various typo fixes
3 Steps to Play
Select your Pokémon Fire Red ROM below and this tool does all the work for you — nothing ever gets uploaded, and it applies the latest v4.1.1 patch automatically.
Add your game file
Your Pokémon Fire Red (U) ROM — the original Fire Red game file. Not an already-patched file, and not a different language or revision.
Tap the big button
Preparing…
Play your game!
Your new game downloads by itself. Open it with a free program called mGBA to play it on your computer or phone.
Prefer to patch it yourself? Download the ZIP for your version above (v4.1.1 recommended) and apply the .ups patch with Rom Patcher JS — see the steps below.
How do I use the ZIP file?
- Download a ZIP from the Download the Files section above — v4.1.1 is recommended.
- Unzip it on your computer. Look for the patch file inside: Odyssey.ups for v4.1.1, or Pokemon Odyssey.ups for v4.0.3.
- Go to the free site Rom Patcher JS.
- Under “ROM file” pick your own Pokémon Fire Red (U) file. Under “Patch file” pick the .ups file you unzipped.
- Click “Apply patch” — it builds your new game file for you to download.
- Open that file with a Game Boy Advance emulator (like mGBA) to play!
Nerd stuff (only if something isn’t working)
No ROM selected yet.
Need Help?
Stuck somewhere? Here are answers to the questions we get asked the most.
Which emulator should I use?
mGBA is the most popular free choice and runs great on PC and Mac (VBA and VBA-M also work). On Android, try MyBoy, PizzaBoy, or Retroarch. On iPhone/iPad, try Delta, 44VBA, or Retroarch. It also runs on handhelds like the Anbernic. Just open your patched game file with any of these and you’re ready to play!
What are the ZIP downloads for?
Those are for the “Prefer to patch it yourself” option below, for people who don’t want to use the button above. Pick v4.1.1 — it’s the newest version with the most fixes. Inside is a patch file (not the full game) that you apply yourself using a free site, along with your own Pokémon Fire Red file. See Download the Files above for sizes and version details.
What’s inside the ZIP file?
Just the patch itself (a small .ups file, not the full game), a HOW TO PLAY.txt with setup steps, and a Documentation folder with quick links to guides for level caps, stats, teambuilding, and wild encounters. The v4.1.1 ZIP also includes a Patch Notes.txt listing what changed.
Which version should I download?
v4.1.1 is the current version and includes every fix from earlier releases, so it’s the one we recommend. v4.0.3 is kept available as the previous build in case you ever need it.
Why did it say my file is wrong?
Our tool double-checks your file to make sure it’s the right one. Make sure you have the original Pokémon Fire Red (U) file — not a different language version, not a rom hack, and not a file that’s already been patched.
My game didn’t download
Take a look at your browser’s download bar (usually at the top or bottom of the screen) or your Downloads folder — some browsers ask you to confirm before saving a file.
Is this safe? Do I have to upload my game?
Totally safe! There are no uploads at all — your game file never leaves your device. Everything happens right there in your browser.
What’s new in this version?
v4.1.1 is the current version — see the full changelog above for everything that changed, including battle fixes and learnset additions. v4.0.3, the previous build, added crash and chest fixes over earlier releases.
About Pokémon Odyssey
Pokémon Odyssey is a story-driven ROM hack built on Pokémon Fire Red. You play as Nyx, a new recruit of the Talrega guild, sent to explore the Yggdrasil Labyrinth — a vast, mysterious dungeon on Talrega Island — alongside your sister Aimée and fellow guild members Ethan and Olympia. Rather than the usual “become a Pokémon Champion” storyline, Odyssey swaps out gym leaders and the Elite Four entirely for guild-based exploration inspired by Etrian Odyssey: mining and gathering points, naval exploration, shop upgrades, and dangerous FOEs guarding the labyrinth’s depths.
Battling gets reworked too. Double battles are the default whenever you have more than one Pokémon, every Pokémon you catch or receive starts with perfect 31 IVs, and EVs come from Power Items and Vitamins rather than grinding wild encounters. The available Pokémon span Generations 1 through 3, including cross-gen evolutions and original “Etrian Variant” regional forms unique to this hack, and you can choose a difficulty level that suits you from the very first town.
Want more detail before you start? Browse the Pokédex for the full Odyssey creature list, check Level Caps to see how difficulty scales through the story, or head to Cheat Codes if you get stuck.