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Pokémon Gold and Silver

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Featured article

Title Screen

Pokémon Gold Version and Silver Version

Developer: Game Freak
Publisher: Nintendo
Platforms: Game Boy, Super Game Boy, Game Boy Color
Released in JP: November 21, 1999
Released in US: October 11, 2000
Released in EU: April 6, 2001
Released in AU: October 13, 2000
Released in KR: April 24, 2002


AreasIcon.png This game has unused areas.
CodeIcon.png This game has unused code.
DevTextIcon.png This game has hidden development-related text.
MinigameIcon.png This game has unused modes / minigames.
GraphicsIcon.png This game has unused graphics.
ItemsIcon.png This game has unused items.
TextIcon.png This game has unused text.
DebugIcon.png This game has debugging material.
RegionIcon.png This game has regional differences.


NotesIcon.png This game has a notes page
PrereleaseIcon.png This game has a prerelease article

Pokémon Gold and Silver is one of the most extensive Pokémon games, featuring 100 new Pokémon (a 66% increase!), new game mechanics like hold items and two new types, and allowing the player to return to Kanto, featured in Red and Blue, as part of the storyline to work his way up to beat the ultimate trainer, Red.

Data

Gen I Mimic Menu

In Gen I, Mimic allowed the player to choose which of the opponent's moves they wanted their Pokémon to copy. In Gen II, the function of this move was altered, and a Pokémon using Mimic simply copies the last move used by the opponent. (Exceptions are made if the opponent didn't use a move on the previous turn, or if its last move was Sketch, Struggle, Metronome, or a move that the Pokémon using Mimic already knows.) Despite the change, the old Mimic menu still exists in the code.

The menu is most intact in the Japanese versions of the games, which still retain the associated text "どのわざを ものまねする?" (Mimic which move?). See for yourself by enabling one of the codes below, then select the FIGHT command during a battle:

  • Gold & Silver (J) - 010111D1
  • Crystal (J) - 010166D2

These codes don't always function perfectly. There are times when the Mimic menu that pops up lists the user's moves, rather than the opponent's. Attempting to mimic a move sometimes causes the Pokémon to use Struggle. It's unknown whether these issues are caused by the player-made codes, or if the menu itself is buggy. Even when the access method works as intended, it's not possible to back out of the Mimic menu.

The leftover menu also works a little differently in the English releases. Once again, it can be accessed by enabling one of the codes below, then selecting the FIGHT command during a battle:

  • Gold & Silver (U) - 01011FD1
  • Crystal (U) - 010135D2

These codes disable the ability to back out of the menu. They also hide the type and PP box, but don't otherwise change the appearance of the FIGHT menu or bring up a list of moves. In Crystal, at least, the game attempts to print text from offset 0x3e61c, but the only thing there is 50, a control character, so no text is displayed. The coordinates that determine where the text at this offset would have appeared on the screen are x=0B, y=0E in BGB, which are identical to the coordinates of the Japanese "どのわざを ものまねする?" (Mimic which move?) message. This suggests that the equivalent English text was removed.

Used Menu (Gen I) Unused Menu (Gen II)
Japanese Japanese English Korean
Pocket Monsters Green Mimic.png Pocket Monsters Kin Mimic.png Pokemon Gold Old Mimic.png Pocket Monsters Geum Old Mimic.png


(Source: Hibiki Ganaha, Torchickens, Wack0)

Mother Naming Function

Pokemon Gold-MotherName.gif

A fully-functional unused feature allows you to name the player's mother. The name itself can be displayed in text via byte 49. It should have 11 tiles reserved in the message box to safeguard against the text overflowing. The mother's name is initialized to MOM when RAM is initialized at boot.

Curiously, during the DUDE's Pokémon-catching tutorial, the player's name is copied over to the same location in RAM where the mother's name is stored. This suggests that either the tutorial didn't exist when the naming mechanism was created, or that players would only have been able to name their mother once the tutorial was no longer accessible.


(Source: iimarck.us)

Unused Pokémon Flight Probability

Some of the Pokémon species in Gen II have the ability to flee from encounters. These Pokémon are grouped into three tables according to how likely it is that they will attempt to escape. While all three tables are used, the first two contain a few species that cannot be encountered in the wild.

(Table 3 consists of only Raikou, Entei, and Suicune, who try to escape 100% of the time.)


(Source: iimarckus, Bulbapedia)

Table 1

There's a 10% probability that Pokémon in this table will attempt to escape. However, the species below are never found in the wild:

  • Eevee
  • Porygon
  • Togetic
  • Umbreon

Table 2

There's a 50% probability that Pokémon in this table will attempt to escape. However, the species below are never found in the wild:

  • Articuno
  • Zapdos
  • Moltres

Unused Battle Types

RAM address D119 determines what type of battle is taking place. Several battle types cannot be experienced during normal gameplay.

Battle Without Pokémon

Battle type 0x02 causes the player to enter battle without sending out a Pokémon. Choosing "FIGHT" or "PKMN" ends the battle instantly, while the "PACK" and "RUN" options function as they normally would.

Unlike the DUDE's demonstration, this battle does not change the player's sprite, automatically throw a Pokéball once the pack is closed, or copy player's name over to the location in RAM where the mother's name is stored.

Battle Female Pokémon Only

Hmmm...
To do:
Get specific DVs.

Battle type 0x05 causes every Pokémon battled by the player to have DVs matching those of a female Pokémon (where possible). Oddly, there doesn't seem to be a corresponding battle type for male Pokémon.

Battle Ends Automatically

Battle type 0x06 ends the battle instantly as soon as the player sends out their first Pokémon.

Though it's inaccessible during normal gameplay, this battle type is still set to trigger if the player attempts to battle a Trainer despite not possessing any usable Pokémon. (You can see this behaviour by using the Bad Clone Glitch to obtain a ????? (FF), letting the Pokémon beneath it faint, and then whiting out.)

Similarly, if the player triggers a wild Pokémon encounter despite not possessing any usable Pokémon, another function unrelated to this battle type causes the battle to end before it starts.

Escape From Battle Impossible

Battle type 0x09 disables the player's ability to flee. While the encounter with the shiny Red Gyarados is impossible to escape from, it uses battle type 0x07, which also ensures that the encountered Pokémon's DVs define it as shiny. (Contrary to popular belief, it is possible to escape from randomly-encountered shiny Pokémon.)

Unused Experience Groups

Hmmm...
To do:
The level 100 experiences don't follow those formulas. Check whether +30 and +70 is supposed to be -30/-70.

How quickly a Pokémon levels up is determined by what experience group its species falls into. The used groups are "Slow", "Medium-Slow", "Medium-Fast", and "Fast". Two additional groups go unused. Pokémon in these groups would have gained experience at a rate similar to those in Medium-Slow, but their maximum EXP would bottom out at a value lower than Medium-Slow's 1,059,860.

Unused Group 1:

  • Growth Rate:
Pokémon GSC ExpType01.png
  • Maximum EXP: 849,970

Unused Group 2:

  • Growth Rate:
Pokémon GSC ExpType02.png
  • Maximum EXP: 949,930


(Source: DevZ)

Unused Field Moves

PKMNGnS-Payday.png

The list of field moves contains two unused entries:

  • 00 - PAY DAY: Apparently, this move could once be used outside of battle. Attempting to use it causes the game to crash, as it was removed from the ability pointer table.
  • 15 - ERROR!: The final entry in the list. No other tables have an entry like this, suggesting that it's another deleted field move. As with PAY DAY, it was removed from the ability pointer table. Attempting to use it has no effect, but it doesn't crash the game. The reason for this is explained down below.

To view these entries for yourself, enter the following GameShark codes and select a Pokémon who knows at least one HM:

  • 0100D5D0 - Pay Day
  • 0115D6D0 - Error!

The ability pointer table has some interesting quirks:

  • The table is a map comprised of unordered ID -> pointer pairs, rather than an array. The reason for this is unclear.
  • The game checks for a terminating entry, pointer 0000. If it encounters this entry before it finds the ID it's seeking, it returns without doing anything further. However, the list doesn't actually contain a terminating entry. As a result, it reads past the end of the list when searching for removed entries Pay Day and Error!, eventually locating an invalid pointer for Pay Day and a terminating entry in the unrelated data that follows the pointer table. This explains why Error! doesn't cause the game to crash.
  • The fact that the keys are out of order suggests that the field move Waterfall was added later on in development. It appears near the end of the list, rather than being grouped with the other HM moves.

Unused Movement Types

Elementary, my dear Cactus.
This needs some investigation.
Discuss ideas and findings on the talk page.
Specifically: What are the others?

Movement types are managed by a byte located at D682 in the English releases of Gold and Silver. Four of the movement types are used:

  • 00: Walking
  • 01: Cycling
  • 04: Surfing
  • 08: Surfing Pikachu

However, there's also one that's inaccessible:

  • 02: At first glance, this movement type looks like the one used when sliding on ice. It's never activated, however, even when the player is sliding around in the Ice Path.

Unused Venomoth Contest Encounter

The game calculates which Pokémon are caught by the other participants in the Bug-Catching Contest using the table below. The table determines the likelihood that each species of Pokémon will be encountered, as well as their potential level range. (The data is identical across Gold, Silver, and Crystal.) The final entry, Venomoth, goes unused. This is likely due to the fact that Venomoth can't be encountered in the National Park.

Offset Encounter
Rate
Species Level
(Min.)
Level
(Max.)
140A0712 20% Caterpie 7 18
140D0712 20% Weedle 7 18
0A0B0912 10% Metapod 9 18
0A0E0912 10% Kakuna 9 18
050C0C0F 5% Butterfree 12 15
050F0C0F 5% Beedrill 12 15
0A300A10 10% Venonat 10 16
0A2E0A11 10% Paras 10 17
057B0D0E 5% Scyther 13 14
057F0D0E 5% Pinsir 13 14
FF311E28 -1% Venomoth 30 40


(Source: Pokémon Crystal Disassembly)

Debug Content

Clock Reset Function

PKMNGnS-Resetclock.png

The localized versions of the games contain a clock reset function that isn't present in the Japanese releases.

Western Version Access

In the western releases, the function can be accessed in two ways:

  1. Press + SELECT + B on the title screen. (No codes required.)
  2. Enable GameShark code 010464CE, then pressing START or A.

In order to reset the clock, the player first needs to input a password. The password varies from game to game, because it is calculated from various game state information. There are a couple options for passwords, as well:

  1. You can use Filb's online tool to calculate the correct password for your current game.
  2. Alternatively, you can change the values at address 23:4225 (or offset $8C225) from 37 to C9 in order to make even incorrect passwords function.
    • If you don't want to do this manually, enable Game Genie code C92-25B-3B6 to achieve the same effect.

If your game's save battery is no longer functional, it's impossible to enter a correct password. Trying to do so causes the game to reset, and triggers a strange graphical bug.


(Source: Phil Erwin)

Korean Version Access

In the Korean releases, the access method has been updated to match the clock reset function in Crystal. Perform the following steps at the title screen:

  1. Press and hold + SELECT + B.
  2. While continuing to hold down SELECT:
    • Release + B.
    • Press and hold + .
  3. Let go of SELECT.

You can also enable GameShark code 010402D0 to achieve the same effect.

To make even correct passwords function, change the values at address 0x4226 from 37 to C9, or just enable Game Genie code C92-26B-3B6.

Debug Maps

Pokemon Gold-ColTest1.png
Debug Menus
Swap your own palettes.

Graphics

Unused NPC Sprite

Hmmm...
To do:
Maybe there's more to it?

Sprite ID 3F is not assigned to any NPC and resembles an old man.

This character appears to have no walking animation, suggesting he may be a character who was never intended to move, such as a sales clerk or a Gym Leader. The character looks similar to both Gym Leaders Chuck of Cianwood Gym and Price of Mahogany Gym.

In order to see this character in-game, the player may enable the Game Genie code 3F4-52A-08A, which will replace the left-most Pokémon Center receptionist in a Pokémon Center's second floor with this NPC. The sprite remains in Pokémon Crystal, where it can be seen using the code 013F54D1.

(Note: For unknown reasons the second code may not work on a real console, but works on v1.5.2 of BGB emulator)


(Source: Pokémon Crystal disassembly project)
(Source: Torchickens (Game Genie code, GameShark code, video))

Video of the unused NPC

Title Screen Palette Oddities

Spaceworld '97 Final (J) Palette Glitch (U)
1999-GS beta title screen.png Pokemon Gold Japanese Title Screen.png Pokemon Gold Ho-Oh different palette.png

The Ho-Oh sprite on Gold's title screen actually uses three colors, suggesting that it was originally intended to appear in all its brilliance instead of as a silhouette. The developers later assigned a palette to it that rendered all three of these colors as black, so its illustrious hues are not normally seen.

You can catch a glimpse of its non-silhouetted appearance by exploiting a glitch that causes the game to reset in mono Game Boy mode on the Game Boy Color, preventing the correct palettes from being loaded. The most reliable way to perform this is by listening to Machop's cry in the Pokédex, then attempting to use the Coin Case.

Contrary to Ho-Oh, Silver's Lugia uses only the two colors visible in-game. This suggests that the decision to render the legendary Pokémon in silhouette was made before Lugia's title screen sprite was created.

Both Pokémon are displayed in color on the title screens of the remakes.

Unused Collision Data

Following the collision data for Ilex Forest (tileset 0x1C), located at 37:7E33 in (J) 1.0, there are 0x60 unused bytes that would allow for 0x18 more blocks than the final tileset contains. The Ilex Forest block data does not have room for an extra 0x18 blocks, which means that it's not entirely clear whether the additional blocks were intended to be part of the collision data for this area. However, since the contents of these extra blocks are static, it suggests that they were. They would have used the following layout, in which each cell corresponds to one fourth of a block, the size of an in-game person:

Solid Walkable
Solid Walkable

Unused Tiles

Tileset 0x06

This tileset is used by Pokémon Centers. It contains blocks for a Gen I-style Pokémon Center that are never used. Below, you can see a reconstruction of a Gen I Pokémon center created by arranging these tiles:

Gen I Gen II
PKMN RBGY PokeCenter.png PKMN Gold Silver TS06 P03 DAY BetaConcept.PNG
PKMN Gold Silver TS06 P03 DAY Betablock.png

The tileset also contains an unused block whose tile has the wrong palette associated with it. As a result, it's red instead of blue.

Tileset 0x15

This tileset is used by caves. It contains an unused mine cart and corresponding tracks. However, no blocks ever use these tiles at all.

PKMN Gold Silver TS15 PB4 DAY.PNG

Tilesets 0x17 & 0x1A

Tileset 0x17, used by the Ruins of Alph, and tileset 0x1A, used by the Hall of Fame, share a 2×2 ground tile. This suggests that tiles may have been shifted from one tileset to another during development.

Tileset 0x17 Tileset 0x1A
PKMN Gold Silver TS17 PB7 DAY.PNG PKMN Gold Silver TS1A PB3 DAY.PNG

The color assignments of the Hall of Fame's tileset also hint at deleted tiles.

Tileset 0x1C

Tileset 0x1C is used by Ilex Forest. It contains two sets of tiles for the signpost, one duplicate and one unused. This was probably a last-minute change, included so as to allow the developers to reverse back at any moment.

PKMN Gold Silver TS1C PB4 NIGHT.PNG

Additionally, Ilex Forest doesn't use any blocks with sand on them, so this standard tile is unused within the forest.

Unused Tilesets

The mock-ups were modeled after this magazine scan.

The games contain unused block and collision data that was used to dump the unused city maps that were leftover from an earlier period of development. The unused block data can be found at 06:6BA0 in (J) 1.0, while the unused collision data is at 06:73A0. They are located after the block data of tileset 0x02, used by the final version of Goldenrod City.

The tileset itself is a mockup based on development leftovers in tileset 01, used by the game's cities, which still contains pagodas parts found at positions identical to the early block data. Only six tiles were added by fans added to produce the mockup tileset.

It seems that the block data was altered after the early city maps were created, copied over to newly-created tileset 0x02, then split to tileset 0x01, and subsequently forgotten about. This is particularly evident in the early Olivine City map, whose lighthouse is now comprised of mountain tiles instead of tower parts.

Additionally, block 0x0D seems to have been removed, causing it to be rendered as a black square in the earlier versions of both Goldenrod City and Olivine.

Tilesets 0x1F & 0x20

Tileset 0x01 seems to have evolved from unused tilesets 0x1F and 0x20, the latter of which seems to be an intermediary stage of progression:

Tileset 0x1F Tileset 0x20
PKMN GS TS1F.PNG PKMN GS TS20.PNG

Tileset 0x1F correctly displays pagodas, while 0x20 correctly displays route house roofs. The original graphics were apparently removed, so these mock-ups were created.

For an explanation of map and tileset naming schemes, please refer to the Notes page.

Unused Tile Palette Assignment Data

Found at 02:4547 in (J) 1.0 are 0x30 bytes that were once used to assign a palette to each tile of a now-removed tileset. The layout has been roughly recreated below, using the second color of each palette to represent its overall appearance:

This palette data seems like it may have been intended to fit tileset 0x09 from Gen I. Perhaps the tileset was ported to Gen II before being removed.

PKMN GS TS RBGY09.PNG

Notice how the carpet featured in tiles 0x37 and 0x38 is blue instead the usual red, which the dark shades of the Game Boy would have suggested.

Items

Dummied-Out Items

Introduction

Many of the item slots in Pokémon Gold, Silver, and Crystal are dummied out, replaced by identical placeholder names and descriptions. The placeholder name varies by region, but the description is always "?".

PKMNGnS-Terusama.png

In the Japan version, the dummied-out items are called "カビチュウ" (Kabichuu). This nonsensical name may be a combination of the "kabi" in カビゴン (Kabigon), the Japanese name for Snorlax, and the "chuu" in ピカチュウ (Pikachuu), the Japanese name for a Pokémon you've probably never heard of.

PKMNGnS-Kabichuu.png

In the Western localizations, the dummied-out items are called "Teru-sama". The Japanese attach "-sama" to the end of people's names to indicate high formality and respect. "Teru" may be a reference to developer Teruki Murakawa, who is credited as a programmer in the western releases, and as a coordinator in the Korean release.

Teru-Sama Korean Gold.png

In Korea, the dummied-out items are known as "?"; a full-width question mark.

These items can be bought and sold at Poké Marts. They cost a whopping ¥39,321, and sell for ¥19,660, roughly half that amount. The price seems less unusual when you consider that 39,321 is 9999 in binary-coded decimal. Binary-coded decimal is the format used by the Gen I games for monetary values, while the Gen II games utilize the plain binary integers format instead. The fact that this placeholder price is in the older format suggests that it's a holdover from an earlier point in development when Gen II used binary-coded decimal as well.

Notable Item Values

Most of the placeholder items are useless, meaning that if you hack one into your inventory, the only options available to you will be "GIVE", "TOSS", and "QUIT". You can force the "USE" option via additional trickery, but the only result is Professor Oak's cautionary "This isn't the time to use that!" That being said, there are three placeholder items with unique effects:

Two of these items are functional holdovers from Gen I:

  • 06: This item is found between the PokéBall and the Bicycle. It works similarly to the Town Map from the original games.
  • 38: This item is found between the Itemfinder and the ExpShare, and functions as a Poké Flute. It can be used to wake up sleeping party Pokémon both in and out of battle, but the "USE" option must be hacked back in. It only triggers the Poké Flute melody when used in the overworld with a sleeping Pokémon in the party. The melody does not play when used in battle, or if the player does not possess a sleeping Pokémon.

The other outlier is BE. Unfortunately, it has an invalid pointer, so it's unlikely that it was ever intended to have a "USE" option.

Elementary, my dear Cactus.
This needs some investigation.
Discuss ideas and findings on the talk page.
Specifically: Are there additional usable placeholder items in other versions?

Crystal-Exclusive Items

Pokémon Crystal introduced several new event items. These overwrote several slots in the item list that had previously contained dummied-out items Gold and Silver.

  • 46: This slot is filled by the Clear Bell in Pokémon Crystal.
  • 73: This slot is filled by the GS Ball.
  • 74: This slot is filled by the Blue Card.
  • 81: This slot is filled by the Egg Ticket.

Gold & Silver were released in Korea much later than the rest of the world, on April 24th, 2002. By this time, Crystal had already been out in Japan for nearly a year and a half. It seems that developers working on the Korean versions took Crystal's existence into account when localizing the games' item text, as they replaced the placeholder names of dummied-out items 46, 73, and 74 with their Crystal equivalents. (For some reason, however, they neglected to rename item 81 to Egg Ticket.) The reason behind their efforts is unclear, however, as the items are still inaccessible in Gold and Silver, and their (lack of) function remains unaltered.

Elementary, my dear Cactus.
This needs some investigation.
Discuss ideas and findings on the talk page.
Specifically: Were the placeholder descriptions updated too?

Other Values

There are a total of 33 dummied-out item values in Gold & Silver, including 26 not mentioned above. See the Notes page for a full list.

Unused Status Prevention Items

There are six unused item effects that, if they were assigned to items which could be held by Pokémon, would have prevented the holder from being afflicted by various status effects. They aren't consumed after use, allowing them to be used indefinitely.

# Effect
14 Prevents the holder from being poisoned, similar to the Immunity ability.
15 Prevents the holder from being burned, similar to the Water Veil ability.
16 Prevents the holder from being frozen, similar to the Magma Armor ability.
17 Prevents the holder from being put to sleep, similar to the Insomnia and Vital Spirit abilities.
18 Prevents the holder from being paralyzed, similar to the Limber ability.
19 Prevents the holder from being confused, similar to the Own Tempo ability.

When activated, 14, 17, 18, and 19 bestow their effect and trigger the text "[Pokémon]'s protected by [Item]!", while 15 and 16 merely bestow their effect without displaying a message.

These items may have been precursors to the status effect prevention abilities that were later introduced in Gen III. They may also be related to the Orb items referenced in a fan account of an early demo that was playable at Spaceworld '97:

"You also started off with 5 Pokéballs, 10 Potions, 10 Full Heals, 1 Stimulus Orb, and 1 Fire-Up Orb. (When equipped by a Pokémon, the Stimulus Orb would occasionally prevent it from falling asleep, and the Fire-Up Orb would occasionally prevent it from fainting.)"

While no effect corresponding to the Fire-Up Orb is present in this list, its Japanese name (Kiai Dama) and function are similar to the Focus Band (Kiai no Hachimaki).

Maps

Pokegold-olivinehouse.png
Unused Maps
Lake of Rage had a gym?

Minigames

Unused Memory Game

There are two kinds of machines in the Game Corner of Gold, Silver, and Crystal: a slot machine and a card flipping table. However, it appears that a memory minigame was also planned. The game can still be hacked back into a functional state. Accessing it requires coins and a Coin Case.

The object of the game is to find matching pairs of cards. If the flipped cards match, they are removed and displayed at the top of the screen. If they don't, both will be flipped back over. The player is given five chances to find matching pairs, after which the cards are dealt anew.

The game has three difficulty levels, determined by the values at CF14. These range from 01 to 03, and likely correspond to a bet of one, two, or three coins. The difficulty levels have an affect on the random placement of the individual card faces.

Many of the routines associated with this game are missing from the code, including the functions that would have allowed players to choose a difficulty level, earn prizes, or even exit the interface. That means that there's no way to win or stop playing, outside of resetting the game entirely.

Additionally, the graphical data for the cursor was commented out, which causes the game to display garbage. (The video on the right uses the PokéGear indicator as a substitute.)

A fully commented disassembly of the memory game is available on the Notes page.

Controls:

  • D-Pad Move the cursor.
  • A Button: Flip the selected card face-up.

Translation:

Japanese Translation Notes
とったもの Cards Acquired Indicates card pairs collected.
あと[#]かい [#] Turns Remaining Indicates the remaining number of attempts.
CARD いただき! Card obtained! Displayed when you get a match.
ざんねん... Too bad... Displayed when you fail to get a match.

Unused Slot Machine Symbol

Identifier 18 is an unused entry in the list of slot machine symbols that references the Bulbasaur doll sprite. There is no defined payout for successfully matching this entry, but you can force the game into trying to give you the three-Bulbasaur payout by enabling the GameShark codes below:

  • 011809C6
  • 01180DC6
  • 011817C6


(Source: Glitch City Forums)

Moves

Unused and redundant Egg Moves

Background Information

Gen II was the first generation to allow Pokémon breeding. In these games, players could drop off a pair of compatible Pokémon at the daycare, then come back after some time had passed to receive an egg.

Whether or not Pokémon were compatible was determined by two factors:

  1. Gender - Only Pokémon of the opposite sex were able to breed with each other. The only exception was the genderless Ditto, who could be partnered with any Pokémon, gendered or not, to produce an egg.
  2. Egg Group - Pokémon were organized by the developers into rough groups according to their physical characteristics. Pokémon who shared an egg group were determined to be physiologically similar enough to successfully breed.

Once the player received an egg, they would have to walk a certain number of steps before the egg would hatch. The resulting offspring shared the species of its mother, and the moveset of its father.

List of Moves

Several Pokémon in Gen II have unused egg moves, which are abilities that can be passed down to a newly-bred Pokémon by its father.

# Pokémon Move Notes
120 Staryu Aurora Beam Staryu is genderless, meaning that it can only be bred with Ditto and can't inherit a parent's moves. These egg moves were removed from Crystal onward.
Barrier
Supersonic
238 Smoochum Lovely Kiss The only Pokémon that can learn Lovely Kiss naturally is Jynx, which is a female-only species. Females couldn't pass down egg moves until Gen VI, and the male Pokémon that were gifted this move via events didn't share an egg group with Jynx. As a result, there is no way for Smoochum to inherit this move via legitimate means. This egg move was removed from Gen III onward.
043 Oddish Charm Charm is an unused egg move on Oddish as there are no legitimate fathers in the Grass egg-group who can learn Charm.


(Source: IIMarckus, 伝説のスターブロブ2, Bulbapedia)

Additionally, Sweet Scent and Steel Wing are programmed as egg moves despite those two moves being TM moves. This makes the data redundant as TM/HM moves are already passed down by the father (in this case TM12 and TM47).

Unused Move Effects

Elementary, my dear Cactus.
This needs some investigation.
Discuss ideas and findings on the talk page.
Specifically: Further research is needed, as this list is likely not exhaustive. Check whether items such as the Poké Doll derive their effects from this list as well. (There are effects that raise accuracy and chance of escape.)

Like their predecessors, Gold, Silver, and Crystal have a number of unused move effects, though none of them seem to deal any damage.

You can test out different effects by modifying the effect of Pound: Just replace the values at 0x41AFF in Gold or 0x41AFC in Crystal with a value from the list below.

# Effect
0C Raises user's Speed by 1 stage.
0E Raises user's Special Defense by 1 stage.
15 Lowers enemy's Special Attack by 1 stage.
16 Lowers enemy's Special Defense by 1 stage.
35 Raises user's Special Attack by 2 stages.
37 Raises user's Accuracy by 2 stages.
38 Raises user's evasion by 2 stages.
3D Lowers opponent's Special Attack by 2 stages.
3E Lowers opponent's Special Defense by 2 stages.
3F Lowers opponent's Accuracy by 2 stages.
40 Lowers opponent's evasion by 2 stages.
8D Causes the opponent to flinch if user is faster, but deals no damage. Always misses if the user is slower, even when Mind Reader was used on the previous turn. (Video here.)

Pokémon

Inaccessible Shiny Variants

Every Pokémon in the game has a Shiny variant, but some of these aren't obtainable via legitimate means.

Mew

The only legitimate way to obtain elusive Pokémon #151 in Gold, Silver, and Crystal was to transfer over a Mew that had been uploaded to a Gen I cartridge at a Nintendo-sponsored distribution event. Unfortunately, every distributed Mew came with a fixed set of DVs that prevented it from becoming Shiny when traded to the next generation.

Shiny Mew (Gold) Shiny Mew (Silver)
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Pokemon Silver Shiny Mew.png

Shiny Mew later became available in Pokémon Emerald. Japanese players were able to obtain an item called the Old Sea Map at one of Nintendo's distribution events, which enabled them to encouter a wild Mew at Faraway Island. This Mew had a regular probability of being Shiny.

Unown

All 28 forms of Unown have Shiny variants, but only "I" and "V" are accessible due to the way Gen II determines this Pokémon's forms and Shininess.

Careful, you'll lose an eye.
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Trainers

Unused Trainer Rosters

Pokémon Trainer Cal, found in Viridian City's Trainer House, is normally only accessible late in the game. Provided that the player didn't use Mystery Gift, he battles the player using Meganium, Typhlosion, and Feraligatr, all at level 50. However, there are two additional rosters associated with this trainer, both of which go unused:

Alternate Roster 1:

  • L:10 Chikorita
  • L:10 Cyndaquil
  • L:10 Totodile

(Video here.)

Alternate Roster 2:

  • L:30 Bayleef
  • L:30 Quilava
  • L:30 Croconaw

(Video here.)

Text

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Unused Text
Gugyoo…

Version Analysis

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Changed Graphics
Details of the graphical changes between release versions.
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Version Differences
Change we can all believe in.