Pokemon PureGreen ROM

Pokemon PureGreen is a Game Boy ROM Hack by Vortiene based on Pokemon Blue. It was last updated on April 10, 2026.

Also, be sure to check out Pokemon Green.

Description

This is a purist’s enhancement of Pokémon Red/Blue/Green. The goal is to enhance the original games for excellent replayability without bringing in mechanics, moves, sprites, visuals, type matchups, or Pokémon that were introduced in later games.

The only version differences between PureRed / PureBlue / PureGreen are visual. Play whatever color you like the most.

Features

• It makes the bulk of the 151 original Pokémon all more obtainable and usable in the early game, with better movesets and more balanced stats.
• Many moves in the game were rebalanced or modified. When the author says “rebalanced”, it means “the useless things were made more useful!”
• There are more bug, poison, and ghost type moves available. The focus is on getting a useful set of moves available for every single Pokémon in the game.
• Front sprites were updated to be just about the best set of sprites from Red/Green/Blue/Spaceworld 1997 overall.
• All 151 Pokémon are obtainable in all versions of this hack.
• HMs are deletable anytime you like and new code to prevent softlocks by deleting them was introduced.
• Some pokemon have additional types, for example, Ninetales is now FIRE/GHOST instead of FIRE. If you don’t like specific type changes, you can change any specific pokemon or all of them back to normal type-wise at an NPC in indigo plateau route 23.
• Many small quality-of-life tweaks and bugfixes were made.
• Game bugs that can be used to your own advantage (like the leech seed/toxic bug, the hyper beam no recharge on faint bug, etc.) are unchanged, because they are quirks of the battle engine that you can use as your own tool.
• Mew is under the truck as expected!
• Missingno and the item duplication glitch are intact – but won’t corrupt your save anymore!
• An entirely new mode for the Pokédex called the MOVEDEX was added. It shows data about moves you have seen in detail. You unlock the MOVEDEX in viridian city.
• There is an arena to rematch gym leaders and other important trainers after becoming CHAMP.
• There are multiple secret areas to be found after becoming CHAMP. Bills Garden, Team Rocket / Mewtwo lore, and more…
• Many options to enhance the game visually and mechanically were added. **(You must turn them on via the options in-game!)** Including:
• Switchable color palettes (Choose between original colors, Super Gameboy Colors, or Pokémon Yellow Colors in-game whenever you like! Works on GBC and Super Gameboy. Yes, this romhack has GBC support!)
• Optional Spaceworld 1997 Back Sprites
• Optional enhanced menu sprites/overworld icons
• Optional enhanced music (Add in cut content music like Giovanni’s theme)
• Optional stereo panned audio (Similar to the Earphone1 option in Pokémon Yellow)
• Optional alternate color palette Pokémon based on region (catch differently colored Pokémon depending on where they appear in Kanto)
• Option to turn off the bicycle song (plays in cycling road still)
• Option to turn on smoother higher framerate fade animations while on the GBC
• Tweak the type matchups to be exactly like gen 1, gen 2, or a cross between them if you like directly in-game.
• Optional in-battle experience bar
• Option to give trainers some Stat EXP to their Pokémon based on level. Makes the game a little bit harder.
• Option to have the game track the PP of opponents (the original game they had infinite PP). Makes the game a little bit easier.
• If you’re playing on GBC and have the palettes set to SGB or GBC mode, move animations will have colors! Surf will be blue, ember will be red, etc.
• There are a couple entirely new things added into the game to facilitate quality of life fixes. Including:
• An NPC who can permanently remove CUT trees.
• An NPC who can revive fossils for you in SAFFRON CITY so you can get fossil Pokémon a bit earlier.
• An NPC who will give you LAPRAS a bit earlier in the game.
• An NPC who will teach you how to DIG in between towns just like you can FLY in between towns.

Changelog

V2.7.2

MINOR TWEAKS

• Sign on the power plant roof now has text instead of nothing
• Lorelei’s second champ arena battle now has higher level pokemon

BUGFIXES

• BUG: Possible to encounter marowak spirits and catch them via glitches FIX: change glitch encounters to these specific pokemon that are supposed to be uncatchable to caterpie
• BUG: Missingno can cause duplication of key items, which can cause them to not be removed when not being needed anymore (secret key, etc) FIX: prevent duplication of key items since it’s pointless anyway
• BUG: White screen after beating fighting dojo master FIX: Fade in correctly before he speaks

V2.7.1

QUALITY OF LIFE

• Can turn on a new option in the 5th options page that will make music resume where it was before a battle after the battle finishes instead of restarting the music completely. Good for when you’re encountering a lot of wild pokemon or battling a lot of trainers in a row. You won’t have to keep hearing the start of the song only.

VISUALS

• Viridian school house b1f was made larger by 1 block on the south side to make it more obvious there is a hallway you can go down.

AUDIO CHANGES

• Can turn on a new option in the 5th options page that will make music resume where it was before a battle after the battle finishes instead of restarting the music completely. Good for when you’re encountering a lot of wild pokemon or battling a lot of trainers in a row. You won’t have to keep hearing the start of the song only.
• Remove the parts of the “hint music” in the secret lab that could confuse the player on what to do and instead just repeat the basic loop.

MINOR TWEAKS

• Rival’s Venusaur gets Siphon Snag instead of Flash in the final battle.
• Safari ball has Great ball’s ball factor 1 now, causing it to be better at catching full health pokemon. Should help in the safari zone’s classic mode.
• In Safari Zone CLASSIC mode, encounter rate will be the original encounter rate of 30 in all areas of the safari zone, in case you want to catch pokemon this way it makes things easier for the player to have the original encounter rate instead of a lower one. Encounter rates will stay lower in the other modes.

BUGFIXES

• BUG: With OG sprites, the poke ball poof can look a bit weird. FIX: Show a definitely blank tile instead of a “sometimes not blank but usually blank” tile.
• BUG: When fighting IRRADIATED in the pokemon tower basement, when it or your pokemon are poisoned by radiation, the HUD doesn’t update immediately. FIX: Draw HUD and HP bars after each pokemon gets poisoned.
• BUG: SGB Mode isn’t working on original hardware. FIX: Add back the full-length delay when doing boot SGB commands, as it appears to be necessary.
• BUG: When viewing pokedex entries without opening the pokedex itself first (like when the guy shows you snorlax’s entry on the SS Anne, Fuchsia Zoo, or picking your starter) metric units will be messed up visually. FIX: Load the metric tiles correctly in this circumstance
• BUG: After evolving a pokemon via rare candy or a stone tiles will be messed up in a map that has replaced tiles like cerulean ball designer’s house. FIX: Load extra tiles in this situation correctly
• BUG: After losing to the karate master in the fighting dojo, the wrong script can be triggered on re-entering the building. FIX: Trigger the after battle script when losing to him as expected.
• BUG: When save transferring, if you have saved mr fuji before transferring, the rocket on the first floor of the pokemon tower is still there. FIX: remove him when loading the map always if you’ve saved mr fuji.
• BUG: If you encounter a pokemon in the power plant exactly on the switch tiles, after coming back from battle, the switch is triggered before it fades in from white, causing the player to not be able to read the text and have to proceed through it before the code fades in. FIX: Fade in when in this scenario.

V2.7.0

NEW AREAS / EVENTS

• Learnsets are now unlockable in the game. You can unlock learnsets after obtaining the MOVEDEX by talking to trainers after you beat them, some trainers may give you info on their pokemon! You can also unlock learnsets by finding books that have details about a specific pokemon on bookshelves, and various other ways by exploring the world! Don’t worry, if you become an expert with a pokemon, you’ll automatically unlock the learnset once you’ve seen its whole learnset by levelling it up if you haven’t gotten it yet! Unlocking a learnset for one pokemon will unlock the learnset for its whole evolutionary family! Select a pokemon in the pokedex and select the MOVE option to view its learnset. You can turn off the learnset feature from the 5th page in the options menu if you don’t want them.
• In Cerulean City, you can now find the POKE BALL DESIGNER! The designer needs help with inspiration to design new poke balls! So grab her camera and take her some pictures of inspiring things in the world! Switch the pokeballs your pokemon are in at her tool bench! MAKE YOUR OWN CUSTOM POKEBALLS WITH CUSTOM AUDIOVISUAL EFFECTS! This is the most in depth poke-ball customization system there’s ever been in a pokemon game! (probably) Unlock 16 poof particles, 16 color palettes, 16 throw animations, 16 poof animations, and 16 sound effects you can all customize. Name your custom pokeballs whatever you want! BECOME A PRO POKE BALL DESIGNER! You can turn off this entire feature from the WORLD OPTIONS.
• In Vermilion City, Celadon City, and Saffron City, you can find “catch-up clubs”! These clubs allow you to train lower level pokemon up to a level cap with triple EXP! If you want to switch up your team during a playthrough, this is a good option to do it quickly! Stop grinding wild pokemon! Pokemon past the level cap won’t receive any EXP in these clubs, and the trainers here won’t make you any money! It’s just for training low level pokemon up! You can turn off these areas via the WORLD OPTIONS menu in the player’s PC.
• In Fuchsia City, there is a new OAK’S AIDE in the SAFARI ZONE meeting room! Talk to her and if you have caught at least 50 pokemon, she’ll upgrade your town map to display wild pokemon data! No need for a wiki, just open your town map and select the place to check what pokemon appear there!
• On Route 12, you can battle a new GAMBLER who loves METRONOME! Embrace the chaos and let him tutor your pokemon the move METRONOME whenever you want!
• Pokemon Center nurses will now recognize you as the CHAMP once you are! They will make amusing comments and treat you as a famous pokemon trainer!
• The Gramps across the water in Celadon City will now tutor your pokemon various moves that used to be TMs instead of giving the meditate TM. Including: SELFDESTRUCT, EXPLOSION, TRI ATTACK, DREAM EATER, PAY DAY, REST, TELEPORT, SOFTBOILED
• There is a new house in SAFFRON CITY that contains the FIGHTING BROS. The FIGHTING BROS want you to get revenge for their FIGHTING DOJO being roughed up by SABRINA! They want you to go beat SABRINA at SAFFRON GYM! Once you do, one of them will tutor you additional moves that used to be TMs: MEGA PUNCH, MEGA KICK, WHIRLWIND, SKULL BASH, SWIFT, EGG BOMB, RAGE, SCREECH. The other one will do you the honour of teaching your ALAKAZAM exactly ONE elemental punch move, and he’ll only do it once because it ain’t easy!
• The Copycat will now repeatedly tutor your pokemon MIMIC after giving her a poke-doll instead of giving you the substitute TM.
• Mr Psychic will now give the Psychic TM again, but he wants you to beat the fighting dojo first!

QUALITY OF LIFE

• In the Front Sprite Options menus, you can now view which sprite you’ve selected for a given pokemon by pressing A or SELECT.
• You can switch between metric and imperial units used in the pokedex from the 5th options page.
• You can set the game to skip the intro animation when booting up the game from the 5th options page.
• You can view STAT EXP in the stats screen of pokemon by pressing SELECT. You can toggle back and forth between stats and STAT EXP.
• You can swap pokemon around in the part menu with SELECT now. It’s a lot faster to do it this way.
• The ITEM menu and PC ITEM menu will now show your remaining bag space left. 15/30, 5/60, etc.
• MAX REPEL now entirely disables wild battles while it’s active (usually you can still encounter pokemon higher than your first pokemon’s level). Makes it better in a way than SUPER REPEL while super repel overall still has a better cost to steps ratio.
• Navigating list menus was improved by improving text printing code. It’s snappier now, and some lists now allow wrapping from top to bottom and holding to scroll faster when they didn’t before. Pokedex and Movedex scrolling speed and rendering speed has vastly improved and it’s a lot smoother.
• Play time hours can now go above 255. They can go up to 10000+ hours now!
• You can turn off Signature Moves now by turning off the “MOVEMYSTIC” option in the world options.
• In elevator floor menus, the current floor is now displayed.
• Improved the speed and responsiveness of the main menu (CONTINUE, NEW GAME, OPTIONS menu after the title screen)
• Removed needlessly long delay when swapping items in list menus with SELECT
• Yes/No menus put the cursor on NO when you press B if it’s not already there for clarity

VISUALS

• You can turn on a new custom title screen for Pokemon PureRGB from the 5th Options page. By default the games use the original title screen.
• Box Art / Label Art is Now Available
• When throwing out a pokemon’s poke ball in battle, the visual effect will be based on which poke ball you caught it in. You can now see GREAT BALLs and ULTRA BALLs, etc. after you catch the pokemon!
• You can also see what ball you caught a pokemon with in the status menu of the pokemon.
• 16 customizable poke balls can be unlocked that have customizable names and animations via the cerulean poke ball designer. They can’t be used to catch pokemon, but you can switch your already caught pokemon into these cool custom poke balls for awesome visual effects!
• See memorable POKEMON TCG game boy art while taking pictures with the Poke Ball Designer’s CAMERA! Recreate the awesome moments caught in these pieces of art with the power of her CAMERA!
• When encountering MEW, there is a new cool animation before the battle starts.
• You lower the amount of flashing during battle/encounter animations by setting that option on the 5th options page.
• STATIC SNAG is now SIPHON SNAG and has a different animation
• Spaceworld Back Sprites improved: Aerodactyl, Scyther, Winter Dragonair
• OG Back sprites added: Winter Dragonair, Volcanic Magmar
• During the winter dragonair event, there will now be an animation when Dragonair powers up
• Secret Lab flower pot keyhole is SLIGHTLY more obvious now

TRAINER AI CHANGES

• Adjustments to avoid using moves that don’t work with the below changes to SMOKESCREEN, SAND ATTACK, and SCREECH

MOVE CHANGES

• SCREECH has an added “screeches echoing” effect, when screeches are echoing during battle, pokemon cannot be put to sleep, and any sleeping pokemon will wake up. It also now never misses. This move is automatically used by a pokemon that has it if an opponent attempts to put them to sleep! Say NO to sleep spam if you want!
• SMOKESCREEN doesn’t affect fire type pokemon. Have some counterplay options to pokemon spamming SMOKESCREEN.
• SAND ATTACK doesn’t affect ground type or flying type pokemon. Have some counterplay options to a pokemon spamming SAND ATTACK.
• HEAT RUSH now has an added 40% chance of raising the SPECIAL stat if the user is a FIRE-type pokemon.
• FILTHY SLAM’s power now goes up to 130 if the target is poisoned.
• STATIC SNAG was reworked into the move SIPHON SNAG. This move is still a 75 power ELECTRIC move, but it has a new effect in which it will heal any status on the user by siphoning energy from the opponent. If the user doesn’t have a status, it’ll heal one of your party member’s statuses! Get rid of statuses by using this move strategically!
• ACID now will always either lower the opponent’s DEFENSE or ATTACK by one stage. Makes it a bit more useful especially when used by ARBOK who has ACID as a signature move.
• LEECH SEED now will do different damage-per-turn depending on the opponent’s resistance to GRASS type. If they resist: 1/16th per turn. If normal effectiveness: 1/8th per turn. If weak to GRASS: 3/16th per turn.
• SKULL BASH now has 100% accuracy if used by a ROCK-type pokemon.
• Arcanine now gets 100% accuracy with FIRE BLAST
• Dewgong now gets 100% accuracy with BLIZZARD
• Golduck’s PSYBEAM increases to 105 power (based on the DARK GOLDUCK pokemon card art)
• TOXIC has 100% accuracy when used by poison-type pokemon.
• Movesets were tweaked to balance with the above changes.
• BLIZZARD is back to 90% accuracy like in Original Red and Blue instead of 85%
• Draining moves now miss on substituted pokemon as originally intended in the code.

AUDIO CHANGES

• FINALLY!!! If you turn on OG+ music mode, the SAFARI ZONE will have a song longer than 10 seconds! Now it’s an entirely new song I composed based on the original one’s melody, and it’s 2 minutes long!
• The “early version of route 3” beta music will now play during in-game trades if you turn on OG+ music mode
• Many new sound effects were added that were used for custom pokeball sound effects
• There is a sound effect now when bill enters the teleporter
• There is a sound effect now when you use PP Up to raise the PP of a move
• Lovely Kiss’s sound effect was improved

MINOR TWEAKS

• Some trainers in GYMs will say different things after you beat the gym leader if what they said no longer made any sense. (3 in Vermilion Gym, 1 in Celadon Gym, 1 in Fuchsia Gym)
• You can now catch additional omanyte/kabuto by fishing at the lowest level of cerulean cave.
• Change Box menu now allows holding the directional buttons to scroll faster, and wrapping from top to bottom.
• Sabrina now gives the Meditate TM instead of the Psychic TM.
• The hiding girl in Silph Co now gives the Substitute TM instead of the Barrage TM.
• In the volcano, the intervals between lava flows on floor 3 were increased slightly (about 3 frames) to make it a bit easier.
• The prospector in the volcano can now explain things again if you didn’t read the first time he explained how to navigate the volcano.
• The Gym Guide now calls you over in pewter gym after you beat brock when you’re walking out. You don’t have to go over and talk to him, it’s just to make people more easily find APEX CHIPs.
• Added a trainer tips sign on route 18 telling the player about pressing SELECT to see stat EXP.
• The warden will say different things to you after you’ve gotten the SURF HM instead of telling you to go get it.
• In game trade owners now have OT names instead of all being called TRAINER.

BUGFIXES

Fixes for Bugs in the original game:

• BUG: While music is fading out picking up an item with instant text wouldn’t show the item pickup text properly. FIX: Override fadeout and play “pick up item” fanfare
• BUG: Sometimes the HP bar color or the pokemon’s status aren’t updated with the right timing FIX: Redraw the HP bars in more situations where they should be.
• BUG: With instant text mode, the “Shrink” sound effect in the new game oak speech wasn’t playing FIX: wait for the menu select sound to finish first.
• BUG: When buying TMs from the game corner prize menu, it instantly closes after you buy something without any feedback. FIX: Display a previously unused feedback message and a play sound effect.

Fixes for Bugs I caused

• BUG: While music is fading out if you do a “fast pokecenter heal” it will freeze up the game until the fading music is done. FIX: Override fadeout
• BUG: In some situations sprite options won’t be saved when starting a new game FIX: back up and restore all possible options
• BUG: When reading Elite Four members’ pokemon teams into memory, indeterminate memory writes can happen due to my crappy code. FIX: Edit my crappy code and ensure that doesn’t happen.
• BUG: Typo in some bills garden text FIX: correct the typo
• BUG: Volcanic Magmar doesn’t get FIRE PUNCH power increase to 105 like normal MAGMAR does. FIX: Update signature moves code to account for the different pokemon index
• BUG: Losing to a Safari Ranger can set the safari zone map to an incorrect current script. FIX: Make it reset scripts like normal trainer battles do correctly.
• BUG: Incorrect white color in the ultra ball palette when using Yellow or Yellow 2 palettes. FIX: use the correct color
• BUG: Learning moves in some events didnt have instant text FIX: force instant text when learning moves menu shows up

Useful Links

Pokecommunity

Github

Reddit