List of glitches (Generation I): Difference between revisions

This is a list of glitches that occur in the Generation I main series Pokémon games.

In Pokémon Red and Green

Prevented progress

If the player's starter Pokémon evolves before they obtain their Pokédex from Prof. Oak, the game will assume, since they have 2 Pokémon registered as caught, that they already have a Pokédex, and will not allow them to proceed. This glitch is only present in the Japanese Pokémon Red and Green.

In Pokémon Red and Blue

Man on roof

If the player does not have the Secret Key to the Cinnabar Gym, and surfs on the east coast and returns to land directly in front of the Gym, a man will appear on the roof of the Gym.

A similar effect happens if the player walks into the Vermilion Gym, walks directly left and then up so that they are facing the bottom-left trash can and press A to inspect it, or if the player is in the gate to Cycling Road. One of the Trainers in the Gym will be misplaced and return to his usual spot once the text box disappears, and when in the gate there may be a man standing on an object somewhere behind the guard.

Both of these variations of this glitch were fixed in some European versions of Red and Blue, such as the Spanish version, as well as all versions of Yellow.

Old man glitch

Main article: Old man glitch

In all Generation I games

--

Main article: -- (move)

0 ERROR

Main article: 0 ERROR

A glitch similar to the Mew glitch that causes Route 6 to become glitched.

0 PP glitch

In Generation I, struggling can be avoided by allowing the game to self-select a move to be used, which can happen to any move used immediately after a Pokémon is defrosted, or due to a handful of moves' effects (Bind, Clamp, Fire Spin, Hyper Beam, Metronome, Mimic, and Wrap) because of the auto-selection involved with partial-trapping moves. A move used with 0 PP in this way would underflow to the maximum possible value, 63 PP, and, due to the way the data is structured, a move that 0 PP Ups had been used on would gain full PP Up status, while those on which PP Ups had been used would lose one PP Up boost. This glitch was addressed in Generation II games and later, which prevent a move from being executed if it has 0 PP.

Cut glitch

Main article: Cut glitch

Cycling Road glitch

If the player does not have a Bicycle (or it has been deposited in the PC), it is still possible to reach Cycling Road by holding down the left button while the guard attempts to prevent the player from entering the Cycling Road. Upon entering Cycling Road, the player will be automatically riding a bike, despite not having one.

Deposit glitch

It is possible for the player to deposit all Pokémon except fainted ones and a black out will occur but only after four steps in the same session. In Red and Blue it is possible to progress further by saving the game before traveling four steps to reset the 'remaining step count' to 4 when the game is reset, though this is no longer the case in Pokémon Yellow because the remaining step count was changed to default to 1 step. The player immediately has a black out if entering a battle with just fainted Pokémon.

Dokokashira door glitch

Main article: Dokokashira door glitch

Draw audio glitch

Prior to Generation II, having the player character draw in a Pokémon battle causes the victory theme to play even though the player has lost.

Dual-typed Pokémon glitch

In Generation I, Pokémon with two types that have a weakness and resistance to the same type receive neutral damage from that type, but the incorrect message is displayed.

For example, Grass-type moves do neutral damage to Gyarados, but if Gyarados is hit by a Grass-type move, the game erroneously states that the attack is "not very effective...".

The game prioritizes on which message to display for each 'special' scenario (where normal damage is not dealt) based on each scenario's internal ordering. The higher the ordering determines what message the game will display. Grass against Water as 200% damage for instance is the 4th entry, whilst Grass against Flying as 50% damage is the 27th. Consequently in this example the game chooses the message for scenario #27, returning the wrong message "It's not very effective...".

If an attack is super-effective against one type and does no damage against another type (for example, Dig against Charizard), the game will erroneously state that the attack missed.

Error codes

Main article: Error codes

Evolutionary stone glitch

	This glitch is in need of research. Reason: Glitch Pokémon which evolve by items You can discuss this on the talk page.

Pokémon can be evolved without the use of an evolutionary stone, provided that the player has sent out a Pokémon with the equivalent identifier of the relevant evolutionary stone item and finishes the battle with that Pokémon in the same battle that a Pokémon that evolves using an evolutionary stone levels up.

Much as the starter Pikachu from Pokémon Yellow will refuse to evolve if a Thunderstone is used on it while in the game it is the starter of, leveling up Pikachu and switching to Growlithe will not cause it to evolve, though outsider Pikachu and Eevee will all do so the same as in Red and Blue.

Some glitch Pokémon with unusual evolutionary flags may evolve this way according to the game 'after exposure to an item', which is not necessarily an evolutionary stone.

Experience underflow glitch

Main article: Experience#Experience underflow glitch

In Generations I and II, level 1 Pokémon using the "medium-slow" growth algorithm will jump from level 1 to level 100 after gaining a low amount of experience points.

Fishing in statues

The player can use a Fishing rod when facing the right or left of a gym statue. It will always say "Looks like there's nothing in here...", except in the Cerulean Gym, where all the Pokémon obtainable in the Gym can be caught. The player is also able to surf on these statues.

Ghost glitch

When encountering a ghost in Pokémon Tower without having a Silph Scope, it is possible to see its true identity by viewing the stats of any Pokémon in the player's party. However, this glitch is only graphical, and it is still impossible to fight or catch it.

Ghost Marowak glitch

Using a Poké Doll on the ghost Marowak in Pokémon Tower with or without the Silph Scope will cause it to permanently disappear.

Hall of Fame glitch

Some corrupted Hall of Fame entries

Main article: Missingno.#Glitches caused

When glitch Pokémon have been seen on the save file, the player's Hall of Fame is badly corrupted with entirely different Pokémon, even glitch Pokémon, and very glitched characters, names and levels. This does not affect the Pokémon themselves, rather the data seen in the Hall of Fame.

Invisible tree

Main article: Cut glitch#Invisible tree

There is a tree near the bottom of Route 14. If this particular tree is cut down and then the player walks five steps west from where the tree was (so that the spot where the tree used to be is at the edge of the screen) and then walks back their path will be blocked as if a tree was still there. Even though the tree is not visible, it can still be cut down normally using the move Cut.

Invisible PC

In Generation I, there is an invisible PC in the hotel in Celadon City. This fact is explained by the close resemblance between the hotel and a Pokémon Center. This was less a glitch, and more likely an oversight by the programmers, who may have forgotten to remove the code to activate the PC at that particular point, though the sprite of the PC itself is no longer there. It is possible to walk on the tile where the PC is.

Leech Seed and Toxic stacking

If the target of Leech Seed is also under the effect of Toxic, Leech Seed damage will increase every turn as the N value of Toxic increases because Leech Seed and Toxic both use the same damage algorithm (N * max(1, int(0.0625*MaxHP). This was fixed as of Generation II. If the current HP of the recipient of Leech Seed's HP-restoring effect is greater than its maximum HP, its current HP will be set equal to its maximum HP.

Gate glitch

Certain gates which can be accessed after the player passes Cycling Road will have guards that restrict the player from passing if the Bicycle is deposited in the PC, even though the player does not require a Bicycle.

Glitch City

Main article: Glitch City

Mew glitch

Main article: Mew glitch

Pewter Gym skip

This glitch occurs in Pokémon Red and Blue. It allows the player to enter Route 3 without defeating Brock at Pewter Gym and earning the Boulder Badge. There are two ways to perform this glitch. Both of these variations were fixed in the Spanish (and possibly other European) versions of Red and Blue.

Walking directly in front of the Youngster

To perform the glitch, the player must first open the menu and move the cursor to "Save" without selecting it. Then the player must walk on the tile in front of the Youngster at the east exit of Pewter City and close the dialogs with the B-button (not the A-button), then immediately press Start and save the game (the cursor is frozen). The player must then reset the game. The conversation will happen again, and the player will then be forced to follow him. After that, the Youngster will be gone, and the player can walk across where the Youngster used to stand to enter Route 3.

Walking a tile away from the Youngster

To perform the glitch, the player must first open the menu and move the cursor to "Save" without selecting it. Then the player must walk past the Youngster at the east exit of Pewter City, leaving at least one empty tile between them, which will allow the player to walk two tiles past the Youngster. The player must then close the dialogs with the B-button (not the A-button), then immediately press Start and save the game (the cursor is frozen). The player must then reset the game. The conversation will happen again, but the player will not be forced to follow him. The player can continue walking along Route 3, but if the player walks into the Youngster's line of sight from the east, they will walk down infinitely.

Pokémon merge glitch

Main article: Pokémon merge glitch

Pokémon storage system cloning

Main article: Pokémon cloning#Storage system method

Rhydon glitch

Main article: Rhydon glitch

Save Surf glitch

The glitch is performed by standing next to a water tile that is facing up, left, or right, walk in that direction and pressing start without letting go of the D-Pad. The game then needs to be saved and reset. When loading the saved data, the player will be facing in the direction that was being held down when the start button was pressed. Using Surf will cause the player to surf on the tile immediately south, even if it is not a water tile.

When loading a saved file, the player usually starts facing south. This is because of the limited data in the game. This glitch causes the player to face in a different direction, which confuses the game.

Selfdestruct/Explosion and Substitute glitch

In Red, Blue, and Yellow using a sacrificial move like Explosion on a Substitute and having the damage break the Substitute prevents the user from fainting. The sprite of the user vanishes regardless.

Silent Indigo Plateau glitch

In the battle against Blue at Indigo Plateau, if the player evolves a Pokémon in battle and defeats Blue, the music will be muted until Professor Oak comes to congratulate the player.

(Video comparing the battle where a Caterpie evolves, to the same battle where no Pokémon evolves):

Sprite glitch

The sprite glitch as seen in Generation I games

The sprite glitch is a glitch that alters the appearance of the sprites in Generation I, making the sprites appear to be cut into pieces or even unrecognizable in some instances.

In Generation I, many glitch Pokémon will distort battle sprites upon their encounter; however, this can be fixed by viewing the stats of a non-glitched Pokémon. There are other methods to the glitch, some of which involve using a Pokémon Center to heal the player's Pokémon when in a glitched area, visiting Glitch City, or catching certain glitch Pokémon.

In other generations, it may occur when a cheating device is used.

Standing on a tree

Red standing on top of the tree outside Vermilion Gym

Main article: Cut glitch#Standing on a tree

In Generation I, if the player cuts down a tree, stands on the spot where the object was, saves, turns the game off, then loads it, the player will be standing on the tree. It is no longer possible to stand on a tree in later generations, nor is it possible to stand on a boulder.

This glitch occurs because the Generation I engine would not store the data needed to remember that the tree had been cleared.

Stuck in a wall

If the player lures an NPC into the grass above Pallet Town, she will block the player from following Professor Oak correctly, causing the player to become stuck in the wall of Oak's laboratory.

Trade cloning

Main article: Pokémon cloning#Trading method

Landing on an NPC

If the player lures an NPC below a ledge that can be jumped over, it is possible to land on top of the NPC.

ZZAZZ glitch

Main article: ZZAZZ glitch

Glitches involving communication with the Generation II games

Johto guard glitch

Main article: Johto guard glitch

Shiny Ditto glitch

The Shiny Ditto glitch requires a game from Generation I and Generation II, but only has an effect on a Generation II game. By trading any Shiny Pokémon to a Generation I game, having a wild Ditto transform into that Pokémon, then catching and trading the Ditto into a Generation II game, the Ditto will be Shiny.

Trade evolution glitch

Generation I Pokémon that can evolve by trading can be taught glitch moves through this glitch. This can be achieved by trading a trade evolution Pokémon from a Generation I game to a Generation II, at a level where its evolved form will learn a move not in Generation I. Trading the Pokémon back to the Generation I game will cause the move to become a glitch move.

For example, trading a level 34 Graveler from Pokémon Red to Pokémon Gold will make the Graveler evolve into Golem. Since it is level 34, it will learn Rollout. If it is then traded back to Pokémon Red, it will still have the move, but the game won't recognize it properly since it is a Generation II move, so will become TM05.

This glitch Pokémon article is part of Project GlitchDex, a Bulbapedia project that aims to write comprehensive articles on glitches in the Pokémon games.