Pocket Monsters Red/Green (Japan) 'dokokashira door' glitch

In late 2006, a video appeared on YouTube demonstrating how to beat the classic Pokémon game in about 7 minutes. This technique can be done on an actual GameBoy and does not require extreme luck or reflexes. However, it works only on Pocket Monsters Red (v1.0) (J) and Pocket Monsters Green (v1.0) (J), the first versions of the game that came out in Japan in 1995.

To explain this route in detail would require many screenshots, so instead I have just embedded the YouTube video on this page.

SGB Pocket Monsters: Green (JPN v1.0) 'warp glitch' in 04:24.37 by p4wn3r.; VBA movie (.vbm) (date: 2010-10-10) MP4 file via BitTorrent (size: 6.1 MB, length: 06:10) Mirror www.archive.org Watch on (www.youtube.com) Submission #2860 — Author's comments Discuss this movie Obsoletes movie #941 (04:24.53) Rating: 6.6 View Publication - Major skip glitch - Final boss skip glitch - Heavy glitch. Pocket Monsters Green (V1.0) (J) S T-Eng0.01LandaR Rom Download for Game Boy at ROMNation.NET Pocket Monsters Green (V1.0) (J) S T-Eng0.01LandaR Filename: Pocket Monsters Green (V1.0) (J) S T-Eng0.01LandaR.zip learn what (U), !, and other rom codes mean.

The following description was originally written by gocha. I have added details where appropriate.

1. Start the game.
2. Obtain two items, きずぐすり (potion) and おとどけもの (Oak's parcel).
3. Open どうぐ (item screen), then point the second item and press Select, B, B.
4. Encounter with a wild pokémon, then open ポケモン (PKMN) screen and press A (selected pokémon will be garbled).
5. Cancel PKMN screen and beat the wild pokémon.
6. Walk in circles for N steps (and stand in front of Gary's house), and enter the house (to emulate the original video, N=83~87).
7. Ash warps to to the area east of Celadon City. Walk into the guardhouse, then out.
9. Take a direct walk into the Pokémon Center of Celadon City, then out.
10. Walk into the entrance four buildings to the left of the Pokémon Center, then out.
11. Move toward the Pokémart, then walk back and forth for 18 steps, then enter the building.
12. Ash warps to Lance's room. Go up to Gary's room.
13. Walk past Gary to meet Professor Oak.

The above route may be the most basic method which you should be able to reproduce. Nonetheless, this route has been improved upon several times by speedrunners (both conventional and tool-assisted). On YouTube, you may find some of the newer videos that beat the game in less than 5 minutes.

Game Resources

The purpose of this page is to document all known tricks of the Pokemon generation 1 games on Game Boy, which include Red, Green, Blue, and Yellow.Table of contents [expand all] [collapse all]

• Luck Manipulation
• Tricks and glitches

• R/G = Red(JPN)/Green
• R/B = Blue(JPN)/Red(International)/Blue(International)
• Y = Yellow

List of categories

Due to the number of categories that exist for Gen 1 Pokemon games, it is helpful to list them here to avoid confusion.

• R/G/B:
  • 'Coop Diploma': [3134] GB Pokémon: Blue and Red Version (USA/Europe) 'Coop Diploma' by MrWint in 3:48:04.1
• Y:
  • branchless (practically 'glitchless'): [3664] GBC Pokémon: Yellow Version (USA/Europe) by TiKevin83 in 1:36:42.31
• R/G/B/Y:
  • 'save glitch' (practically 'any%'): [2687] GB Pokémon: Red Version (USA/Europe) 'save glitch' by MrWint in 01:09.95
  • 'game end glitch' (practically 'no save corruption'): [3901] GBC Pokémon: Yellow Version (USA/Europe) 'game end glitch' by TiKevin83 in 09:47.92
  • 'Gotta Catch 'Em All!' (works as full-completion): [3687] GB Pokémon: Blue Version (USA/Europe) 'Gotta Catch 'Em All!' by luckytyphlosion in 37:55.33
  • 'arbitrary code execution': [3358] GBC Pokémon: Yellow Version (USA/Europe) 'arbitrary code execution' by MrWint in 05:48.28

Luck Manipulation

In RBGY/GSC (assuming fast text speed), thetiming of a button press has a high influence on random factor.The duration of a button press (how long it is held down) hasa mild influence on random factor. For example, holding a button downfor different durations usually (but not always) preservesa critical hit while randomizing damage. Mashing the A button duringdialog slows down the text a little, so it can be used to luck-manipulate.

In RBGY/GSC, when catching Pokémon, timing of entering squares has a high influence on random factor. Walking around in the grass without stopping has a mild influence; the desired type of Pokémonis not likely to change, but its DVs are likely to change. Duration of a button press also has a mild influence.

Most actions are determined when they are needed; for example, criticalhits are determined when the damage is calculated, and attack misses aredetermined at the end of the attack message. However, there are a few thingsto watch out for:

(Game Mechanics)

• When both Pokémon have the same speed, all things being equal, the one going first is decided when the attack is selected in the menu.
• When using Quick Claw (1/4 chance to go first if slower, all other things being equal), in GSC, the chance is determined when the attack is selected, but in RSE, it is determined before the menu appears.
• Paralyze effect (unable to move) is determined just before the attack is attempted, and confusion effect (self-damage) is determined after '(Pokémon) is confused!'
• In RBGY and RSE, added effects of attacks (flinch, stat boost, confusion, paralyze, etc.) are determined after the hit, after critical hit and super effective messages if any. In GSC, added effects are determined when calculating damage.

(AI)

• Enemy Pokémon moves are determined when the attack is selected.
• Trainer moves are determined before the menu appears.
  • Smart trainers will always use stronger attacking moves over weaker ones.
  • Smart trainers will always try to use moves that knock out your Pokémon if it is possible.
  • Smart trainers may also do things like use potions or switch to a Pokémon that resists your last attack.
• In GSC, it may be possible to manipulate the trainer Pokémon order. The choice of Pokémon is determined after experience dialogs from knocking out the previous Pokémon.
  • The first Pokémon is always fixed.
  • Smart trainers will always bring in a Pokémon that can knock out your Pokémon if it is possible, and will always avoid bringing in a Pokémon that is weak to yours.
  • In RBGY, Pokémon order cannot be manipulated.
  • In RSE, Pokémon order can only be manipulated from what your current Pokémon is, not from luck-manipulation.

Pokemon Green Version

(Overworld)

• Some things like the direction that a randomly looking trainer looks, as well as people movement, can be manipulated.
  • In RSE, trainers that change the direction in which they look are influenced by running near them. It is required to walk or bike by them to avoid triggering a battle.
• Wild Pokémon encounters are determined when you step into a patch of grass.

(Pokémon personal stats)

• Personal stats (DVs/IVs, nature, ability, shiny, Pokérus, etc) for the starter Pokémon are determined when you obtain the Pokémon.
• Personal stats for wild Pokémon are determined on encounter.

(Other)

• (RSE) Zigzagoon's Pickup ability is determined on the fadeout after each battle.

Random Number Generator (RBGY)

Memory addresses FFD3 and FFD4 are the two RNG bytes. The I/O address FF04 (which may be anything) influences theses addresses in the following way:

• New FFD3 is FFD3+FF04 or FFD3+FF04+1
• New FFD4 is FFD4-FF04 or FFD4-FF04-1

Note that FFD3+FFD4 (the D-sum) either increases by 1 (in battles), decreases by 1 (in overworld), or remains constant. These changes occur many times per frame.

Random encounters are determined by the value of FFD3 and FFD4 as follows:

• Encounters occur if FFD4 < D887 (which is usually $0F).
• Which Pokémon encountered is determined by FFD3.

Pokémon Index by Area	FFD3 range
0 (common)	0-50
1	51-101
2	102-140
3	141-165
4	166-190
5	191-215
6	216-228
7	229-241
8	242-252
9 (rare)	253-255

It may be necessary to change the D-sum to be able to catch different Pokémon. This can be done by waiting one or two frames to clear a dialog in battle. Pressing A in the field can have an effect, but slows you down two frames.

During battle, FFD3 controls damage (not in an obvious way) and FFD4 controls critical hits. Both may be responsible for controlling accuracy. Delaying button presses produces large changes, and holding A in a dialog usually has a mild effect (which is why critical hits sometimes remain), but may occasionally produce a large change.

Tricks and glitches

Pokédoll glitch (RBGY)

Non-100%-accuracy glitch (RBGY)

Missingno. Pokémon and relatives (RBGY)

Not much is known about Missingno. (name is derived from “missing number”)other than that it glitches the game badly.Encountering a Missingno. automatically gives you 128 more of the item in thesixth slot of your pack (if it isn’t already above 127). In addition, Missingno.writes garbage to the savefile on encounter, messes up graphics,possesses abnormal stats and moves, has strange evolution lines, and does unpredictable things to the game.

Missingno. relatives: ‘M, Missingno., other glitch Pokémon of a high ID number,glitch trainers.

Missingno. is related to the ZZAZZ glitch.

Cinnabar Island glitch (RBG)

Also known as the Missingno. glitch. The east coast of Cinnabar Island (and Seafoam Islands) is a defined grassy encounter spot (which must be surfed), but has no defined encounter list. Instead, Pokémon from the previous grassy encounter list are used. This includes, for example, Safari Zone Pokémon if it was the last grassy area you traveled in. However, if you talked to the guy in Viridian who teaches how to catch a Weedle, and saw him catch a Weedle, your name is placed in the encounter list, which, when doing the glitch, may cause glitch Pokémon (or normal Pokémon with absurd levels) to appear:

• characters #3, #5 and #7 (marked with P) will define the Pokémon;
• characters #2, #4 and #6 (marked with L) will define the experience level;
• the first character has no effect at all;

See Table of Pokémon ID numbers.

This glitch does not work in Yellow version.

Trainer-Fly glitch (RBGY)

This glitch is also known as the Mew glitch.The basics of this glitch is that some of the trainers that battle you havea line of sight that is up, left, or right and sees you if you start onesquare past the line of sight (with the trainer offscreen) and walk onesquare toward the trainer. During this one-square-walk, the game defaultsthe trainer to facing downward before rendering the trainer in the properdirection, allowing you to open the menu and escape rope/dig/fly/teleportaway as the trainer sees you. This will suspend the pre-battle trigger.

After you perform this, you cannot control your character except with thedirectional keys. To regain control, let a trainer see you but let the trainerwalk up to you, so that control is regained after the battle. Fight other trainersand even wild Pokémon if you desire. Now walking back to the area where thepre-battle trigger occurred will trigger a magic wild Pokémon encounter(after you close the menu that pops up). This Pokémon's level is the Attack stat modifier (from -6 to +6) plus 7 (so for normal Attack stat modifier 0, level is 7).Which Pokémon this is depends on the special of the last Pokémon that you battled.

See Table of Pokémon ID numbers.

Skipping Snorlax (RBGY)

By performing the Trainer Fly glitch following certain rules both Snorlax blockades in the game may be skipped.

The rules for how this glitch works are as follows: ^[2]

Pocket Monsters Green Version J V1.0 Codes

• The object that ends up disappearing is the last vanishable object encountered before the menu pops up at the end of the trainer-fly glitch. This can be a legendary pokemon (e.g. Snorlax), a character (e.g. guard in Saffron), or an item (e.g. antidote on Route 1). It may be encountered before trainer-fly is initiated, during the time the start button is disabled, or even after the start-button is reactivated.
• A room has at most one vanishable object, and that object is 'encountered' just by entering the room even if the object does not appear on-screen. If this one object has already been removed, in the end the glitch has no effect. On route 1, this one object is the antidote. In Saffron City, this is the guard blocking the way to Copycat. Thus, it does not seem possible to remove either of the other two guards in Saffron.
• Many places such as Vermillion City have no vanishable objects. This is a good thing.

Experience underflow on fading-experience Pokemon (RBGY)

Depending on the level-experience relationship a Pokemon has, each level corresponds to a certainamount of experience. For fading-experience Pokemon E = 1.2L³ - 15L² + 100L - 140, where Eis the experience corresponding to level L. However, for L=1, E=-54. So if a fading-experience level 1 Pokemon is glitchedby using Trainer-Fly (lowering the Attack stat modifier of the previous Pokemon as far as possible),it will have -54 experience, which the game interprets as 16777162 experience. Gaining 53 or less experiencewill cause its level to reset to L100.

Pocket Monsters Green Version J V1.0 Pro

Pokemon with fading-experience are Mew and all 3-stage-evolution Pokemon except the Caterpie and Weedle lines.

Masking Pokémon cries with the low health sound (RBGY)

Pocket Monsters Green Version J V1.0 Rom

Glitch City glitch and walk through walls glitch (RBGY)

First, enter the Safari Zone. Exit and when asked to leave say 'no'. Save the game and reset. Then leave and when asked to enter say 'yes'. Leave through the bottom exit. Walk or bike 500 steps and you will be returned to the Safari Zone building. Exit and you will be in Glitch City.

If, however, you are halfway over a ledge jump before you are warped back, you can walk through walls at the Safari Zone building until you exit. Even more, if your last non-fainted Pokemon faints from poison while in the Safari Zone building, you are warped outside, where you can walk or bike over anything, even water, until you enter a building. This has many applications, such as:

• Getting to Cinnabar without Surf.
• Getting to Saffron Gym with a guard in the way.
• Bypassing Victory Road (go west of Viridian, then north).
• Skipping the first and last badge checks, thus not being required to do those gyms.

Skip Pewter City gym (RBG)

Approach the Youngster that forces you to Pewter gym (but don't walk in front yet). Open the menu and select 'Save', but don't save. Now walk in front of him and as soon as you close the last dialog with B (A doesn't work), immediately press Start and save the game (the cursor is frozen). Reset the game. Then the conversation will happen again; let him take you. After that, go back to where the Youngster should be and he should no longer be in the correct position. Walk through where he should have been and you have skipped the Pewter City gym.

You must do any item buying beforehand, since entering a building resets the Youngster's position.

Because of the walk-through-walls glitch above, you don't need the first badge, because you can skip the first badge check.

This glitch does not work in Yellow version.

Useful memory addresses (RBGY)^[3]

Addresses listed are exact for Red/Blue US versions. Yellow is the same memory address minus 1.

CFE7: Current HP of current opponent.

CFF1: DVs of current opponent. This is used to determine theDVs of wild Pokémon that you want to catch.

CFF4: Stats of current opponent (except current HP). First is the total HP,followed by attack, defense, speed, and special.Each value is two bytes.

D0D8: Amount of damage current attack is about to do.Damage is rolled directly after the entire “- used such-and-such” dialog is displayed.A very nice thing about this is, one frame before the actual damage is calculated,the maximum damage possible is also stored in this memory location, which can helpyou to plan attacks and to know what exactly is possible or not.^[4]

D186: DVs of the first Pokémon in your party. This is for your starting Pokémon.

In-game time:
DA40: Hours, two bytes.
DA42: Minutes, two bytes.
DA44: Seconds, one byte.
DA45: Frames, one byte.

FF04: I/O address used by the RNG for entropy.FFD3: RNG byte. Controls type of Pokémon in an encounter, and damage during battle.FFD4: RNG byte. Controls Pokémon encounter events, and critical hits.

See also

[2] Thanks to hanzou for this explanation.

[3] Credit goes to primorial#soup who found the memory addresses.

[4] primorial#soup’s description.

See also

• Game Resources ― we have resource pages for other games too!
• Common Tricks ― tricks common to many games
• Boss Fighting Guide ― tricks specific to boss fights