Pokemon Emerald 20 ROM

Pokemon Emerald 20 is a GBA ROM Hack by Emcee Mikey based on Pokemon Emerald. It was last updated on May 05, 2025.

Description

Pokemon Emerald 20 is a celebration of 20 years of the best gen, and 3 separate iterations are planned. The first iteration is just the base game with 20 types introduced. Pokemon Emerald is one of my favorite Pokemon games of all time, along with Scarlet and Let’s Go Pikachu. I’ve recently begun to learn how to romhack thanks to the fine folks over at Team Aqua’s Hideout, and while I have more ambitious plans for a future hack, right now I’m happy to share that I’ve been working on a small vanilla+ hack that exists for two main reasons: first, to get myself familiar with the decomp; and second, as a personal appreciation project for the amazing franchise that Game Freak brought to the world. EMERALD 20 is nearing completion and will be complete this summer! So, what’s the gimmick of this hack? Well, since it’s Emerald’s 20th anniversary, I thought it would be fun to round up to a nice even 20 types. Two new types have been added to the game, AURAL and ASTRAL.

Aural-type is a special type that focuses primarily on sound waves but also extends to include other types of inaudible waves. Moves like UPROAR, GROWL, and SONICBOOM are Aural-type, of course, but so are moves like FOCUS BLAST, AURA SPHERE, and VACUUM WAVE.

Astral-type is a special type that focuses on Pokemon from “out-of-town.” This type is very rare, and it’s worth going out of your way to catch some of these Pokemon. MOONBLAST, METEOR BEAM, and SWIFT are some examples of Astral-type moves.

I also made Dragon-type physical. This is a slight buff to Dragonite

The goal of this hack is to recapture a bit of that nostalgic feeling that playing Emerald off and on for the past 20 years has brought me.

Think of it as an amateur mod of Pokemon Emerald that might have been made in 2005, with the benefit of some of the future changes Game Freak themselves made. I hope people who play this hack are willing to approach it with an open mind and a sense of whimsy. For this reason, an exact list of everything I’ve changed in the game will not be forthcoming. I want people who play this hack to explore and discover everything that EMERALD 20 has to offer.

Features

• A celebration of 20 years of Pokemon Emerald
• 20 new types introduced
• Refurbished story
• Introduces two new types: Aural (sound/wave-based) and Astral (space-themed)
  
  • Aural-type is a special type that focuses primarily on sound waves but also extends to include other types of inaudible waves. Moves like UPROAR, GROWL, and SONICBOOM are Aural-type, of course, but so are moves like FOCUS BLAST, AURA SPHERE, and VACUUM WAVE.
  • Astral-type is a special type that focuses on Pokemon from “out-of-town.” This type is very rare, and it’s worth going out of your way to catch some of these Pokemon. MOONBLAST, METEOR BEAM, and SWIFT are some examples of Astral-type moves.
• Dragon-type is now physical, buffing classic Pokémon like Dragonite
• Heavy focus on double battles and Gen 3 VGC-style gameplay
• References and mechanics inspired by Pokémon Colosseum and XD: Gale of Darkness
• New battle formats and unique strategic challenges
• Early playable build; more event content to be added

Changelog

05-05-25

• Introduces two new types: Aural (sound/wave-based) and Astral (space-themed)
  
  • Aural-type is a special type that focuses primarily on sound waves but also extends to include other types of inaudible waves. Moves like UPROAR, GROWL, and SONICBOOM are Aural-type, of course, but so are moves like FOCUS BLAST, AURA SPHERE, and VACUUM WAVE.
  • Astral-type is a special type that focuses on Pokemon from “out-of-town.” This type is very rare, and it’s worth going out of your way to catch some of these Pokemon. MOONBLAST, METEOR BEAM, and SWIFT are some examples of Astral-type moves.
• Dragon-type is now physical, buffing classic Pokémon like Dragonite

27-05-24

• Updated pokemon and move types to include aural and astral
• Made the aural type innately soundproof- implementation is buggy
• Stripped, weirdly named sound moves from level up learnsets
• Removed soundproof from nearly all Pokemon- most of these Pokemon were given aural type to compensate

Useful Links

Pokecommunity

Reddit

Discord