Pokemon Odyssey

Download Pre-Patched Pokemon Odyssey GBA ROM Hack

• Creator: PacoScarso
• Version: 4.0
• Hack of: FireRed
• Updated: June 17, 2025
• Language: English
• Status: Completed (includes the full main story, the postgame, and all three unique endings)

Pokemon Odyssey is a GBA ROM Hack by PacoScarso based on Pokemon Fire Red in English. And it is now available to download. It was last updated on June 17, 2025.

Introduction

Hello people! Long story short: this is a crossover project between Pokémon, Made in Abyss, and Etrian Odyssey. It’s a sort of dungeon-crawler story-driven, but you don’t need to know anything about Etrian Odyssey or Made in Abyss to fully enjoy this game!

Synopsis

On the island of Talrega lies the entrance to the Yggdrasil labyrinth, a gigantic desert carved from the roots of the tree of life over millennia; filled with treasures and other valuable items, it attracted explorers from everywhere. 

What are you looking for? Fame? Money? Or do you just want to test your coaching skills by tackling the maze? Is there something deep down?

In this game, you’ll play as Nyx, a young adventurer who wants to challenge the labyrinth.

But as soon as she starts descending, something goes wrong…

Narrative Arcs

• Strata 1-2 (v1.0) ➜ Part 1: Between the Azure Skies and Seas
• Strata 3-4 (v2.0) ➜ Part 2: What Lies in the Abyss
• Strata 5-6 (v3.0) ➜ Part 3: Truth, Despair and Hope
• Strata 7-8 (v4.0) ➜ Part 4: The Final Boundary

Features

• New Story and Region
• New Graphics (Sprites, Tilesets, etc)
• No Gym Leaders/Evil Team/Elite Four, it’s time to explore!
• Every Pokémon has been rebalanced
• New regional forms: the Etrian Variants!
• Shared Experience
• Two Initials Minun and Plusle.
• The first 3 generations of Pokémon and their 4th generation evolutions are available, as well as extras like Farigiraf.
• All Pokémon present received a new learnpool and the weakest mediums received buffs and adjustments to bring them to the level of the others
• 3 selectable game modes are available in the prologue: Picnic, Normal, and Hard
• Presence of Etrian Odyssey features such as Mining and Gathering points, Naval Exploration, FOE, and Store Upgrades
• Sidequests and a sidequest menu
• Wonder Trade
• All Pokémon, both trainer and wild, will have 31 IVs in all stats to decrease the grind
• You get no EVS from beating a Pokémon, instead you’ll have to use Power Items or Vitamins (for a lowered price)
• You can change the nature and the ability of your Pokémon using in-game functions
• The labyrinth is divided into layers and each of them has a captain that must be defeated if you want to continue
• Adding part of the movements of subsequent generations
• Pokémon nature is highlighted in the various menus
• EVs-IVs screen available in the Start menu
• The automatic stroke can be activated and deactivated by pressing the “L” key on the GBA Emulator
• All fights in the game will be doubles, except when you have only one Pokémon
• Pokemon will not give EVs when defeated. Indeed, it will be necessary to use vigor tools and vitamins (from the reduced price)
• There is a soft level cap to prevent players from making me too much and ruining the gaming experience
• Cannot use healing tools in combat unless held (like berries)
• There is a Prodigious Exchange system in the Talrega guild
• Exp. Share Gen VI style as a game mechanic
• Infinite TMs
• New soundtrack.

Characters

  NYX

• A young adventurer that wants to challenge the Yggdrasil Labyrinth.
• Good at Pokémon battles, she tries to follow in her sister’s footsteps in order to surpass her.
• Signature Pokémon: Plusle & Minun

  AIMÉE

• The best explorer from the Adventurers Guild in the city of Talrega and Nyx’s older sister.
• She’s the one that wrote the majority of books and guides regarding the labyrinth, its treasures and mysteries.
• Signature Pokémon: ???

  ETHAN

• An introverted and awkward boy who will travel with Nyx during her adventure.
• He has a mysterious connection with Aimée.
• Signature Pokémon: Kecleon & Shroomish.

  OLYMPIA

• A strange girl who will travel with Nyx during her adventure.
• She claims to be a robot and acts like one.
• She has a mysterious connection with Aimée.
• Signature Pokémon: Mawile & Porygon

Supported Emulators

• PC/MacOS: mGBA, VBA, VBA-M;
• Android: MyBoy, PizzaBoy, Retroarch (mGBA core), Lemuroid;
• iOS: 44VBA, Retroarch (mGBA core).

Save File Compatibility

Q: Are save files compatible between versions?

A: Yes, they are! To use your old save file with a new version, just make sure that both the .gba file and the .sav file have the same name (for example, Odyssey.gba and Odyssey.sav) and are placed in the same folder. The emulator will do the rest and load your save file.

If you’re having trouble with your save files after updating the ROM, follow these steps carefully:

1. Save in-game using the in-game menu, then close your game.
   • Do not use save states when switching ROMs—this can cause problems and is not supported.
2. Find your old ROM file (e.g., Odyssey.gba).
   • Move it to a different folder to avoid filename conflicts.
3. Get the new ROM file (e.g., by patching as explained in your setup guide).
4. Move the new ROM file to the same folder where your old ROM was originally.
5. Rename the new ROM to match the exact filename of the old ROM.
6. Open the new ROM in your emulator.
   • Your emulator should now load the old .sav save file with your updated ROM.

Following these steps ensures that your old save data works with the new version of the ROM.

Changelog – What’s NEW!

4.0.1

• Fixed some dialogues,
• Fixed some movement permissions,
• Fixed a bug regarding the Lavender Town ghost encounter in the 8th Stratum,
• Fixed an issue in Jagged Mountain,
• Fixed an issue with the Dex not showing the wild mons in the Sandy Caves,
• Fixed an issue that was preventing Vulpix from appearing in the wonder trade,
• Fixed an issue with Octazooka and Needle Arm’s priority,
• Fixed an issue with Call: Owl’s effect,
• Removed the double confirmation from MementoVitae

Screenshots

Useful Stuff

Downloads

Previous Versions

Credits

• PacoScarso ➜ Creator
• Magiscarf ➜ Tilesets
• Aveontrainer ➜ Battle Backgrounds
• The-Red-eX ➜ Tilesets
• Ekat ➜ Tilesets
• Pyvetal ➜ Tilesets
• Aloeva ➜ Regional variants’ concept art
• Mediko ➜ Regional variant’ concept art and sprite
• Swonkfish ➜ Pixel art, regional variants’ sprite
• kWharever ➜ Battle Backgrounds
• BadassBill ➜ Tilesets
• Kyledove ➜ Tilesets
• Kalarie ➜ Sprites (OW)
• shinyzura ➜ Improved trainer sprites
• Avon, SphericalIce, DoesntKnowHowToPlay, FBI, Daniils, Squeetz, Jambo51, VersekrDark ➜ Asm

Beta Testers

Hapu, FlamingDragonGaming, LanturnJoe, Nah.png, Prof. A. Malgam, Streyar, Dekadent, Hallan, Seraphim, Ayato612, Yuni-1311, Zachsz, .fennec., Drextruction, Swonkfish, MissMidori, BurningMyDread, Meomite, Ponk, Ayrei, Vytron, Saiph, Flygon, Lusio, Dr. Jaska, Mediko.