Pokemon Emerald Imperium

If you finished Radical Red and wished someone had given Hoenn the same treatment, Pokemon Emerald Imperium is the closest thing to that wish. It is a difficulty hack of Pokemon Emerald made by iriv24 on top of the pokeemerald decomp and the RHH pokeemerald-expansion engine. The creator openly lists Radical Red as the inspiration — abilities, stat tweaks, learnsets and evolution methods follow the same modernised philosophy — while stating that the two projects are not affiliated.

The story still follows Emerald, but the fights around it have been rebuilt. More than 100 trainer battles were reworked, with the heaviest focus on Gym Leaders, the Elite Four, rivals, Team Aqua and Magma, and mini-bosses scattered across routes. Several optional boss trainers sit off the main path for players who want extra pressure. On the default Normal mode the Bag cannot be used in trainer battles and the battle style is locked to Set, so you cannot heal your way through a bad matchup or get free switches after a knockout.

Imperium also borrows characters and ideas from Sinnoh. Dawn shows up as an additional rival, the Sinnoh Gym Leaders appear (only Roark is required to progress), and some Gen 4 music made it into the game. Mega Evolution is available, including custom Megas the creator designed — among them Megas for the Gen 4 starters and a few former Gigantamax forms converted into Mega Evolutions.

The first full release, v1.0, covered the whole game from the opening route to the Champion plus post-game content. Updates since then have focused on fixes and balance, and the most recent public build is v1.3.1, updated on 4 September 2025. Almost every Pokemon from Generations 1 to 9 can be caught, although a few legendaries were still on the to-do list at the time of that release.

• Two difficulty modes: Normal (intended, no Bag in trainer battles, forced Set style) and Easy (bosses 2 levels lower, Bag allowed, Shift style available)
• Built-in level caps, plus a second nurse in every Pokemon Center who can raise a Pokemon straight to the current cap
• Configurable Minimal Grinding Mode: perfect IVs and no EVs, or random IVs with free EV/IV editing
• In-game randomizer with fully random, base-stat-scaled and legendary-aware species modes; boss trainers are never randomized
• Almost all Pokemon from Gens 1-9, with Radical Red-style stat, ability and learnset changes
• Mega Evolution with custom Megas, including the Gen 4 starters and Gigantamax forms turned into Megas
• Dawn as an extra rival and the Sinnoh Gym Leaders as new opponents
• DexNav, toggleable follower Pokemon and a Gen 5-style summary screen that shows EVs and IVs
• Type effectiveness icons and a move power display in battle, plus Sleep Clause
• Heavy quality of life: reusable TMs, HMs not needing to be taught, PokeVial healing, PC anywhere, infinite Repel and auto-run toggles

Normal mode is where Imperium wants you to play. Bosses use competitive-style teams with held items and natures that make sense, and with no Bag access you need a plan before the fight starts. Players coming from Radical Red Normal mode will feel at home; players whose last Pokemon game was vanilla Emerald will probably lose a few battles before the second gym.

Easy mode exists for people who like the modern features but not the stress. Bosses drop two levels, you can use items and Shift switching is unlocked. One reviewer at Retro Dodo pointed out that the challenge is not perfectly even — some fights fold quickly while others lean on trial and error — so expect a few walls rather than a smooth curve.

Because the randomizer leaves boss trainers untouched, Imperium also works well for randomized Nuzlockes: route encounters change every run while the boss fights you have to plan for stay predictable.

• Use mGBA on PC, or Pizza Boy, Lemuroid or RetroArch with the mGBA core on mobile. The release notes warn that VBA and My Boy can cause graphical glitches and crashes.
• Decide on Minimal Grinding Mode before you leave the house: with it on, every Pokemon already has perfect IVs, so you can focus on team building instead of hunting stats.
• Visit the second nurse after each badge to bring new catches up to the level cap instantly.
• Check boss teams by losing once on purpose if you are not playing a Nuzlocke — with no items in battle, knowing the lead and the speed tiers matters more than raw levels.
• Collect the care packages: they contain infinite Rare Candy, type-boosting items and resist berries that make preparation much easier.
• Do not update mid-run unless you have to; the creator notes that some new content or trainers may not be reachable on an older save.

After the complete v1.0 release, versions 1.1 to 1.3 were mostly maintenance: DexNav fixes, balance adjustments and changes to the ability randomizer, which had some abilities removed from its pool. Updating a save in the middle of a run re-rolls randomized abilities, so finish an ability-randomized run on the version you started it on.

v1.3.1 from September 2025 is the build to download today. The full changelog is kept in a Google Doc linked from the creator's release post rather than inside the game.