Pokémon Gold and Silver

Pokémon Gold Version and Silver Version
Also known as: Pocket Monsters Gold & Silver (JP/KR) Developer: Game Freak Publishers: Nintendo (JP/US/EU/AU), Daiwon C&A (KR) 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 This game has unused areas. This game has unused code. This game has hidden development-related text. This game has unused modes / minigames. This game has unused graphics. This game has unused items. This game has unused music. This game has unused text. This game has debugging material. This game has regional differences. This game has revisional differences. This game has a development article This game has a prototype article This game has a prerelease article This game has a notes page This game has a bugs page This game has a Data Crystal page

Some of the most extensive Pokémon games, featuring 100 new Pokémon (a 66% increase!), new mechanics like held items and two new types, and even allowing the player to return to Kanto, featured in Red and Blue.

Sub-Pages

Development Info

Prototype Info

Prerelease Info

Notes

Bugs

Resources

Debug Menus Swap your own palettes.

Unused Graphics Gym Leaders really need to up their game.

Unused Text Gugyoo...

Unused Trainers No battle with Prof.Oak this time.

Unused Maps The Lake of Rage had a Gym?

Version Differences

Version Differences Changes we can all believe in.

German Demo Version Einige geringfügige Unterschiede.

Unused Move Data

Leftover Mimic Menu

Used Menu (Gen I)		Unused Menu (Gen II)
Japanese	English	Japanese	English	Korean

In Generation I, Mimic allowed the player to choose which of the opponent's moves they wanted their Pokémon to copy. In Generation II, the function of this move was altered, with it simply copying the last move used by the opponent. However, despite the change, the old Mimic menu still exists in the code, most intact in the Japanese versions of the games, which still retain the associated "どのわざを ものまねする?" (Mimic which move?) message. This unused menu can be seen by using the FIGHT command with the following codes:

Gold & Silver (J)	Crystal (J)	Gold & Silver (U)	Crystal (U)
010111D1	010166D2	01011FD1	010135D2

This menu is slightly buggy, as 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, and even when the access method works as intended, it's not possible to back out of the Mimic menu.

(Source: Hibiki Ganaha, Torchickens, Wack0)

Unused Move Effects

Generation II has a handful of unused move effects which can be seen by replacing the values at 0x041AFF in Gold and Silver (0x041AFC in Crystal) and using the move Pound. Effect 8D is the only one that's really interesting as it always misses if the user is slower, even when Mind Reader was used on the previous turn, as seen here.

#	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. Deals no damage

(Source: Pokémon Gold and Silver Disassembly)

Unused Field Moves

The list of field moves contains two unused entries:

• PAY DAY (00): 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.
• ERROR! (15): The final entry in the list, with it also being removed from the pointer table much like Payday. Attempting to use it has no effect. This is because if the game encounters a terminating entry before it finds the needed ID, it returns without doing anything further. And since the list lacks such entry, it reads past it and eventually located an invalid pointer for Pay Day, and a terminating entry in the unrelated data that follows the pointer table.

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

Pay Day	Error!
0100D5D0	0115D6D0

Unused Battle Data

Unused Battle Types

What type of battle is taking place is determined by RAM address D119. Several battle types cannot be experienced during normal gameplay.

Battle Without Pokémon
Battle type 02 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. Unrelated to the DUDE's battle demonstration.

Battle Female Pokémon Only
Battle type 05 causes every battled Pokémon to have DVs matching those of a female Pokémon, when possible. There is no corresponding battle type for male Pokémon.

Battle Ends Automatically
Battle type 06 ends the battle instantly as soon as the player sends out their first Pokémon. Though 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 behavior 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.

(Source: ChickasaurusGL)

Unused "Send Out" Animations

In addition to the existing variants 00 (send out Pokémon) and 01 (send out shiny Pokémon), two extra unused animations exist, dating back to the Spaceworld '97 demo:

• Variant 02 causes the Pokémon to fade into battle after coming out of its Poké Ball. Originally assigned to Hoothoot. Rather buggy in the final games. Labelled as "Jiwajiwa" in the code, which means slowly.
• Variant 03 causes the Pokémon to slowly wave into battle. Not assigned to any Pokémon in the demo, but seen used by Blastoise in prerelease footage. Labelled as "Yurayura" in the code, which means waving.

(Source: ChickasaurusGL)

Unused Pokémon Data

Unused Egg Moves

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

#	Pokémon	Move	Notes
120	Staryu	Aurora Beam	Staryu is genderless, meaning that it can only be bred with Ditto and thus can't inherit a parent's moves. In the Spaceworld '99 demo, both Staryu and Starmie were gendered, making these leftovers from that build. 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. Mothers 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 for Oddish as there are no legitimate fathers in the Grass egg-group who can learn it. However, if Cubone and Marowak had not lost access to this move after the Spaceworld '97 demo, it would have been possible to chain-breed Charm onto Oddish (Marowak -> Bulbasaur -> Oddish).
143	Snorlax	Charm	Same case as with Oddish; there are no legitimate fathers in the Monster egg group who can learn Charm. The only Pokémon in the Monster egg group that can learn Charm, Nidoran♀, is a female-only species. As a side note, Cubone and Marowak were able to learn Charm in the Spaceworld 1997 demo but lost access to it in the final, so if the two kept it they could have theoretically passed the move down. It's possible this was a leftover of that time.
001	Bulbasaur	Charm	Same as above; there are no legitimate fathers in either the Grass or Monster egg groups who can learn Charm. It's also another possible leftover from when Cubone and Marowak could learn it.

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 being TM12 and TM47. Specifically, Sweet Scent is an egg move for Paras and Shuckle, while Steel Wing is an egg move for Pidgey, Farfetch'd, Aerodactyl, and Natu.

(Source: Pokémon Gold and Silver Disassembly)

Unused Flight Probabilities

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 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

(Source: Pokémon Gold and Silver Disassembly)

Unused Experience Groups

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:
  
• Maximum EXP: 849,970

Unused Group 2:

• Growth Rate:
  
• Maximum EXP: 949,930

(Source: Pokémon Gold and Silver Disassembly)

Unobtainable Shinies

All 26 forms of Unown have shiny variants, however, in a funny coincidence, only "I" and "V" Unown can be shiny due to both Unown Forms and Shininess being dependent on IVs. These are the only instances of truly unused shinies, as while the Pokémon Egg technically has a placeholder shiny palette, it is but a copy of its regular one.

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Unused Minigames Data

Memory Game

There are two kinds of Game Corner machines in Generation II': a slot machine and a card-flipping table. However, other minigames were planned, but were ultimately cut, with the memory game from the Space World '97 demo being all that remain in the final games. This game can still be hacked back into a functional state, and accessing it requires game 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 correspond to a bet of one, five, or ten coins. The difficulty levels have an effect on the random placement of the individual card faces.

Many of the routines associated with this game are missing from the final games, including the functions to choose a difficulty level, earn prizes, or even exit the game. 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 also commented out, which causes the game to display garbage, with the video provided here using 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
<CARD>　いただき！	<CARD>, yeah!	Displayed when you get a match.
ざんねん...	Darn...	Displayed when you fail to get a match.
とったもの	Cards acquired.	Indicates card pairs collected.
あと<TURN#>かい	<TURN#> turns left.	Indicates the remaining number of attempts.

(Source: Pokémon Gold and Silver Disassembly)

Unused Slot Symbol

Sitting at 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)

Unobtainable Room Decorations

Gold and Silver were the first games in which the player can obtain various kinds of in-game furnitures to decorate their room. The majority of them are received by using the Mystery Gift option with either a copy of Gold, Silver, or Crystal, or by using the Transfer Pak with a copy of Pokémon Stadium or Pokémon Stadium 2. However, three of the Generation II decorations are unobtainable through normal means, with them being planned exclusives to Pokémon Stadium 2.

The Coin Case glitch exclusive to Gold and Silver makes it possible to obtain these items, through the use of a particular setup.

Tentacool Doll and Pikachu Bed

In Pokémon Stadium 2, decorations are sorted in a rarity table containing three sets:

• Gift Set 1 (Common) awards the player either a Big Lapras Doll or a Surf Pikachu Doll.
• Gift Set 2 (Rare) awards the player a Tentacool Doll.
• Gift Set 3 (Very Rare) awards the player a Tentacool Doll if Round 2 hasn't been unlocked, and a Pikachu Bed if it has.

However, due to the way Stadium 2 handles random number generation, only the first set is ever utilized. Given the fact that these decorations are unused due to an oversight, they function as intended when hacked into either Stadium 2 or the mainline Gen II games. The Tentacool doll's graphics are not technically unused due to it reusing a frame of Tentacool's menu icon (like the other dolls), though the Pikachu Bed's unique tiles are never seen anywhere else.

Unown Doll

Weirdly enough, a doll styled after Unown exists, but isn't part of any item gift tables. It appears to not be fully implemented, since while it does have a unique "room viewer" model in Stadium 2, when sending it over the game will state that "DECORATION was transferred", instead of "UNOWN DOLL was transferred". Like the aforementioned two unused decorations, this one also works as intended in the mainline Gen II games, with it appropriately reusing the first frame of Unown's menu icon, and having a proper name in the PC.

(Source: Project Pokémon Forums)

Unused Miscellaneous Data

Mother Naming Function

Rather interestingly, there exists a fully-functional option that allows you to name the player's mother. It was first seen in the dummied-out story mode of the Spaceworld '97 demo, where Silver offers you a choice between three set names, or the option to choose your own name. This scrapped interaction was likely made to showcase the PokéGear's cellphone functionality, as the player could then receive calls from their mother, with the game displaying the name they had chosen for her. 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 set to MOM when RAM is initialized at boot.

Interestingly, 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 the naming mechanism was already unused by the time the tutorial was created.

(Source: IIMarckus)

Placeholder PokéGear Contacts

Indices 08-0A and 19 in the PokéGear's phone directory are unused contacts named "----------". They are located within the range of valid phone indices (01-24), much like how the MissingNo. from Gen I are located within the range of valid Pokémon. Attempting to call any of these contacts via hacking only brings up the message that they are out of reach.

GameShark code 01xxC6D9 will replace the first contact in the directory for US Gold and Silver.

(Source: Glitch City Laboratories PhoneDex project, pigdevil2010, Hakuda2 (JP))

Unused Trainer Card Page

Found among the code for the Trainer Card are remnants of a planned, but ultimately scrapped third page, which would have been used to display the Kanto Badges, just like what the second page does with the Johto badges. While only incomplete code remains in the retail games, the source code leak did provide some corresponding graphical assets.

.KantoBadgeCheck: ; unreferenced
	ld a, [wKantoBadges]
	and a
	ret z
	ld a, TRAINERCARDSTATE_PAGE3_LOADGFX
	ld [wJumptableIndex], a
	ret

(Source: Pokémon Gold and Silver Disassembly)

Unused Roof Palette Data

The various houses found throughout Kanto and Johto all have a given roof type and roof palette assigned to them. Unsurprisingly, some of them end up going completely unused in the final games. The palettes below are listed as morning, day, and then night respectively:

Used as a placeholder for maps that aren't assigned a set roof palette. As such, it doesn't have a dedicated roof type (the New Bark Town roof is used here for clarity's sake).

Uses the roof type assigned to Kanto, only with the Ruins of Alph palette applied. Is assigned to the Indigo Plateau, which in the final games doesn't even have any roof visible.

Uses the roof type assigned to Kanto, only with a red palette applied. Is assigned to Cinnabar Island, which in the final games only uses the flat grey Pokémon Center roof.

(Source: Helix Chamber)

Unused Tileset Palette Data

Found at 02:4547 in (J) 1.0 are 30 bytes which once assigned a palette to a now-removed tileset. This palette data is virtually a perfect match to tileset 09 from Generation I. This tileset being ported to Gen II before being removed makes sense given how the Pewter Museum was originally supposed to make a return in Gold and Silver. Worth noting is how the carpet featured in tiles 37 and 38 is blue instead of the usual red. Its layout has been recreated below, using the second color of each palette to represent its overall appearance:

(Source: Pokémon Gold and Silver Disassembly)

Unused Blockset Data

The games contain unused block and collision data, which can both be found in (J) 1.0 at 06:6BA0 and 06:73A0 respectively. Located after the block data of tileset 02, this blockset is a leftover from an earlier period of development, where it was used for the original Johto overworld. While the corresponding tileset and palette data are nowhere to be found, the metatile data reveals that it used an earlier version of tileset 01, which in the final games is used for the majority of the Johto overworld. Notably, it makes use of the leftover pagoda tiles, with them looking much closer to their Space World '97 counterparts. Within the leaked source code, this blockset is known as HILLCEL.CEL.

(Source: Pokémon Gold and Silver Disassembly)

Unused Fly Location

Among the list of "fly points" is an unused entry for Route 10. While you couldn't fly directly there in Generation I, it appears that the devs originally wanted it to be possible in Gold and Silver. However, the flag used to make this route a possible fly location is never enabled at any point within its map script. However, the "Warp" debug option does let the player be transported to Route 10.

Worth noting is that when the aforementioned flag is set, and one tries to fly to this route, its landmark header on the Town Map will be "ROCK TUNNEL", instead of "ROUTE 10". Other than that, it works just as intended, spawning you right in front of the Pokémon Center.

(Source: Pokémon Gold and Silver Disassembly)

Unused Environment Type

Each and every map is assigned an "environment type", which dictates certain parameters, such as displaying the current time palette, or restricting what the player can do (like use Fly while inside a cave). A total of seven types exist, but the fifth one goes unused in the final games. It is programmed to show the morning/day/night colors (like in the overworld), but restricts the use of Fly, Teleport, Dig, the Escape Rope, and the Bicycle. The source file IMG_TYPE.DEF refers to this entry as pimg_SHIP, suggesting that it would have been used for a ship deck, something which the S.S.Anne features, but that its Gen II successor, the S.S.Aqua, lacks entirely.

(Source: Pokémon Gold and Silver Disassembly)

Unused Event Scripts

The following maps contain bookshelf scripts that are redundant, as they redirect to a set of flavor strings that are already defined:

• The Good Rod house in Olivine City: PictureBooks.
• Mania's house in Cianwood City: PictureBooks.
• The house in Mahogany Town which speaks about the Red Gyarados: PictureBooks and Magazines.
• The house in Blackthorn City which speaks about Clair and Lance: PictureBooks and Magazines.
• The house Route 2 where you can get a Nugget: DifficultBooks
• The Super Rod house on Route 12: PictureBooks.
• The Name Rater's house in Lavender Town: DifficultBooks.
• The Fishing Guru's house in Vermilion City: PictureBooks.

Meanwhile, the maps listed here contain the following scripts, despite never needing them:

• Professor Elm's Lab has data redirecting to the standard trash can message, but never uses it as a unique message is used instead.
• Ilex Forest has data related to Strength boulders, despite not containing any. Only cuttable trees are present in this map.
• The flower shop in Goldenrod City has data for the PictureBooks and Magazines flavor text, as well as a radio event for the LuckyChannel script. However, neither a pair of bookshelves nor a radio are present in the final version of this map.
• Route 41 has data related to Rock Smash rocks, despite not containing any. However, Route 40 and Cianwood City do contain those.
• The Magikarp Enthusiast's house by the Lake of Rage has sign data which redirects to a blank text entry. This may have been intended to display the current Magikarp size record. However, in the final games, the Fishing Guru NPC is the one who states the record.

(Source: Pokémon Gold and Silver Disassembly)

Unused Movement Scripts

The table below documents maps whose scripts contain unused movement data, which would have been used to move the player or other characters during cutscenes.

Map	Data	Notes
Cherrygrove City	step LEFT turn_head DOWN	Found near the end of the move data for the Rival encounter. The source file for this map, T21.EV, labels this script as anm_rival_goto_hero_t21_02.
Mahogany Town	step DOWN big_step UP turn_head DOWN	Found right before the move data for the Rage Candybar salesman. The source file for this map, T28.EV, labels this script as anm_hero_buck_t28.
Route 40	step RIGHT step UP step UP step UP step UP step UP step UP step UP step UP step UP step UP step UP step UP step UP step UP step UP	This map doesn't feature any other movement data. The source file for this map, R40.EV, labels these scripts as anm_swimmer_r40_01 through 03. This tells us that these are leftovers from a scene, possibly related to Surf, involving a male swimmer (their female counterpart being internally known as "bikini").
Fast Ship 1F	step UP step DOWN	Found before the player's move data related to the worried grandpa scene. The source file for this map, P01R0301.EV, labels these scripts as anm_hero_up_p01r0301 and anm_hero_up_p01r0301.
Game Corner (Celadon City)	step RIGHT turn_head LEFT	This map doesn't feature any other movement data. The source file for this map, T07R0401.EV, labels this script as anm_shopman02_t07r0401_01. This tells us that this is a leftover from a scene involving a male clerk (their female counterpart being internally known as "counterw").

(Source: Pokémon Gold and Silver Disassembly)

Unused Item Get Scripts

The maps below contain the TM/HM reward message, but they're redundant as the game internally redirects to the standard "<PLAYER> received <TM/HM><#>" message instead:

• Route 36 - TM08.
• Moomoo Ranch - TM13.
• Olivine Gym - TM09.
• Route 43 - TM30.
• Rocket Hideout - HM06.
• Blackthorn Gym - TM24.
• Dragon’s Den - TM24.

Blackthorn City's gym is rather interesting, as it contains not only the TM 24 message twice, but also Clair's dialogue where she says that she wants us to have this TM, as well as the dialogue afterwards where she describes it. This is obviously never used, as Dragon Breath can only be obtained in the Dragon's Den, which suggests that originally Clair didn't ask the player to bring her a Dragon Fang. Funnily enough, this dialogue can be seen in Crystal with the right setup.

(Source: Pokémon Gold and Silver Disassembly)

Unused Skating Movement Type

Movement types are managed by a byte located at D682 in the US Gold and Silver. Their names are taken from the source code. Four out of five movement types are used in-game:

• 00: Walking (MODE_WALK)
• 01: Cycling (MODE_BICYCLE)
• 04: Surfing (MODE_RAPLUS)
• 08: Surfing Pikachu (MODE_PIKA)

This leaves 02 unused, with it being the movement type for the cut Skateboard originally found in the Spaceworld '97 demo, accessible via that build's debug menu. It is labeled in the source code as MODE_SKATE. The skate data is also found commented out next to the bicycle data.

(Source: Pokémon Gold and Silver Disassembly)

Unused Collision Types

The collision constant list is a tad messy, being filled with either garbage entries or duplicates of already existing ones. However, there exist some noteworthy collision types which are never used in normal gameplay.

#	Name	Notes
30	COLL_CURRENT_RIGHT	Surfing on a block with this type pushes the player one tile to the right, acting as current. Has a duplicate at 38.
31	COLL_CURRENT_LEFT	Surfing on a block with this type pushes the player one tile to the left, acting as current. Has a duplicate at 39.
32	COLL_CURRENT_UP	Surfing on a block with this type pushes the player one tile up, acting as current. Has a duplicate at 3A.
41	COLL_WALK_RIGHT	Stepping on this block makes the player walk one tile right. Has a duplicate at 50.
42	COLL_WALK_LEFT	Stepping on this block makes the player walk one tile left. Has a duplicate at 51.
43	COLL_WALK_UP	Stepping on this block makes the player walk one tile up. Has a duplicate at 52.
44	COLL_WALK_DOWN	Stepping on this block makes the player walk one tile down. Has a duplicate at 53.
A2	COLL_HOP_UP	North-facing ledges are never seen at any point during the game, leaving this collision type unused.
A6	COLL_HOP_UP_RIGHT	North-facing ledges are never seen at any point during the game, leaving this collision type unused.
A7	COLL_HOP_UP_LEFT	North-facing ledges are never seen at any point during the game, leaving this collision type unused.
B3	COLL_DOWN_WALL	A land tile with this collision type will act as if the tile south of it is a wall, regardless of its actual collision type.
B4	COLL_DOWN_RIGHT_WALL	A land tile with this type acts as if the tiles south and east of it are walls, regardless of their actual collision.
B5	COLL_DOWN_LEFT_WALL	A land tile with this type acts as if the tiles south and west of it are walls, regardless of their actual collision.
B6	COLL_UP_RIGHT_WALL	A land tile with this type acts as if the tiles north and east of it are walls, regardless of their actual collision.
B7	COLL_UP_LEFT_WALL	A land tile with this type acts as if the tiles north and west of it are walls, regardless of their actual collision.
C0	COLL_RIGHT_BUOY	A water tile with this type acts as if the tile east of it is a wall, regardless of its actual collision.
C1	COLL_LEFT_BUOY	A water tile with this type acts as if the tile west of it is a wall, regardless of its actual collision.
C2	COLL_UP_BUOY	A water tile with this type acts as if the tile north of it is a wall, regardless of its actual collision.
C3	COLL_DOWN_BUOY	A water tile with this type acts as if the tile south of it is a wall, regardless of its actual collision.
C4	COLL_DOWN_RIGHT_BUOY	Same behavior as B4, but water-based.
C5	COLL_DOWN_LEFT_BUOY	Same behavior as B5, but water-based.
C6	COLL_UP_RIGHT_BUOY	Same behavior as B6, but water-based.
C7	COLL_UP_LEFT_BUOY	Same behavior as B7, but water-based.

(Source: Pokémon Gold and Silver Disassembly)

Unused Headbutt Encounter Set

While only two encounter sets are used for Headbutt trees ("Forest" and "Canyon"), there exists a third, unused type. Labeled as "City", it is actually assigned to five Johto cities, including Blackthorn, which used to have Headbutt trees earlier in development. Oddly enough, the final games skip this set entirely, and trying to use Headbutt on a tree found within a city will never trigger an encounter. Worth noting about this "City" set is that the Pokémon listed are at level 15 (instead of 10, like the used Headbutt sets).

Encounter Rate	Common Table	Rare Table	Level
50%	Venonat	Venonat	15
30%	Venonat	Magnemite	15
10%	Abra	Abra	15
5%	Abra	Abra	15
5%	Venomoth	Venomoth	15

(Source: Pokémon Gold and Silver Disassembly)

Unused Contest Encounter

These games use a special table to generate Pokémon that are encountered during the Bug Catching Contest. The table determines the likelihood that each species of Pokémon will be encountered, as well as their potential level range. However, the final spot, assigned to Venomoth, goes unused, as the percentages add up to 100% before that entry is reached.

Hexadecimal Data	Encounter Rate	Pokémon 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 Gold and Silver Disassembly)

Unused Static Entei Encounter

The basement of the Burned Tower contains data for a scrapped static encounter, which would have allowed one to fight against a level 40 Entei. No corresponding data exists for the other two Legendary Beasts, and in the final games, they were all made to be roaming Pokémon. This encounter data is likely from earlier in development, where the Beasts were static encounters, not unlike the Legendary Birds of Kanto.

(Source: Pokémon Gold and Silver Disassembly)

Unused Trade Data

This data was originally used as a debug function intended to test out trading. When enabled, it prompts an auto-trade between two characters, known as ゲーフリ (Game Freak) and クリーチャ (Creatures), the two default Player and Rival names from Japanese Blue's debug mode. The original trainer names of these Pokémon, meanwhile, are a reference to Kōji Nishino (the inspiration behind Snorlax, known in Japanese as "Kabigon") and Toshinobu Matsumiya, who is listed in the credits of Gold and Silver under Game Scenario.

This unused trade still remains in Crystal, where it is still as unused as before.

Sent Pokémon		O.T.	ID
	Venusaur	かびーん (Kabīn)	08961
Received Pokémon		O.T.	ID
	Charizard	マツミヤ (Matsumiya)	22020

(Source: Pokémon Gold and Silver Disassembly)

Unused Sound Effects

The final games include the two unknown fanfares from the Space World '97 demo. Their sound IDs are 0x92 and 0x2D, respectively.

Unused Items

Dummied-Out Items

Japanese	English	Korean

Many of the item slots in Generation II are dummied out, and replaced by identical placeholder data. Their name varies by region, but the description is always "?". In the Japanese versions, these blank items are called "カビチュウ" (Kabichu), a cutesy nonsensical which is likely a combination of "カビゴン" (Kabigon, Snorlax's Japanese name) and "ピカチュウ" (Pikachu). In the Western localizations, these items are called "Teru-sama", composed of the Japanese honorific "-sama" and Teruki Murakawa, who is credited as a programmer in the Western releases and as a coordinator in the Korean release. 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 when Gen II still used binary-coded decimal as well.

Cut Item List
Additional information regarding the items originally assigned to these IDs can be found here.

#	Name	Notes
06	Teru-sama	Originally occupied by the Town Map, a leftover from Generation I.
19	Teru-sama	Originally occupied by the Leftovers, which was later moved to ID 92.
2D	Teru-sama	Originally occupied by the Bitter Berry, which was later moved to ID 53.
32	Teru-sama	Originally occupied by the Gold Berry, which was later moved to ID AE.
38	Teru-sama	Originally occupied by the Poké Flute, a leftover from Generation I.
5A	Teru-sama	Originally occupied by a duplicate of the Gold Berry.
64	Teru-sama	Originally occupied by the Berry, which was later moved to ID AD.
78	Teru-sama	Originally occupied by a duplicate of the Berry.
87	Teru-sama	Originally occupied by a duplicate of the Berry.
88	Teru-sama	Originally occupied by the "Ice Bikini", a cut item from the Space World '97 demo.
89	Teru-sama	Originally occupied by the "Thunder Fang", a cut item from the Space World '97 demo.
8D	Teru-sama	Originally occupied by a cut item named "Steel Scales".
8E	Teru-sama	Originally occupied by a cut item named "Mystic Shell".
91	Teru-sama	Originally occupied by the "Water Tail", a cut item from the Space World '97 demo.
93	Teru-sama	Originally occupied by the "Ice Wing", a cut item from the Space World '97 demo.
94	Teru-sama	Originally occupied by the "Thunder Wing", a cut item from the Space World '97 demo.
95	Teru-sama	Originally occupied by the "Fire Wing", a cut item from the Space World '97 demo.
99	Teru-sama	Originally occupied by a cut item named "Ancient Power".
9A	Teru-sama	Originally occupied by the "Fire Tail", a cut item from the Space World '97 demo.
9B	Teru-sama	Originally occupied by the "Thunder Tail", a cut item from the Space World '97 demo.
A2	Teru-sama	Originally occupied by the "Poison Stone", a cut item from the Space World '97 demo.
AB	Teru-sama	Originally occupied by a cut item named "Tickle Stick".
B3	Teru-sama	Originally occupied by a cut item named "Honey Pot".
BE	Teru-sama	Originally occupied by a duplicate of the Berry.
BF - C2	Teru-sama	Unknown.
C3	Teru-sama	Originally occupied by a duplicate of the Berry.
C4 - C6	Teru-sama	Unknown.

Crystal-Exclusive Items
Several new event items were later introduced in Pokémon Crystal, and these overwrote several slots which previously were occupied by a Teru-Sama:

• ID spot 46 was overwritten by the Clear Bell.
• ID spot 73 was overwritten by the GS Ball.
• ID spot 74 was overwritten by the Blue Card.
• ID spot 81 was overwritten by the Egg Ticket.

Gold and Silver were released in Korea much later than the rest of the world, and 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 into account when localizing the games' item text, as they replaced the placeholder names of items 46, 73, and 74 with their Crystal equivalents (though for some reason they neglected to rename item 81 to "Egg Ticket"). The reason behind these changes is unclear, however, as these items are still inaccessible in Gold and Silver, and their (lack of) effects remain unaltered.

(Source: Pokémon Gold and Silver Disassembly)

Unused Item Effects

A good handful of unused item effects exist in the final games, some of them having interesting mechanics:

• There are six unused item effects that shield the holder from status effects. They aren't consumed after use, allowing them to be used indefinitely.
• There are seven unused item effects that raise one of the eight Pokémon "stats", similar to the X-Items. Each item is used up after the effect is applied to the Pokémon and is only in effect as long as the Pokémon stays in battle.
• There are five unused item effects that, when assigned to a held item, will be consumed upon use but trigger no effect.

#	Effect
02	Item is consumed upon use, but no effect is triggered.
05	Item is consumed upon use, but no effect is triggered.
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.
1E	Item is consumed upon use, but no effect is triggered.
1F	Increases the holder's Attack by 1 stage, similar to the battle item X Attack.
20	Increases the holder's Defense by 1 stage, similar to the battle item X Defense.
21	Increases the holder's Speed by 1 stage, similar to the battle item X Speed.
22	Increases the holder's Special Attack by 1 stage, similar to the battle item X Special/X Sp. Atk.
23	Increase the holder's Special Defense by 1 stage, similar to the battle item X Sp. Def.
24	Increase the holder's Accuracy by 1 stage, similar to the battle item X Accuracy.
25	Increase the holder's Evasion by 1 stage, similar to the move Double Team.
26	Item is consumed upon use, but no effect is triggered.
46	Increase the Catch Rate when the item is held by a Pokémon.
47	Item is consumed upon use, but no effect is triggered.

When activated, 14, and 17 to 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. The effects of 1F to 25 are only triggered if the holder is damaged by an attack (damage from poison or recoil will not activate them), and will consume the item on use. The effects of 02, 05, 1E, 26, 47 will only trigger the consumed effect when not assigned to a Berry or other consumable item. 46 is unique as it doesn't work properly and only shows up as a "used" hold item effect in the disassembly. All item effects above 4F will do nothing.

Some of these unused effects were actually originally used in the Space World '97 demo:

• ID spot 47 was used by the Flee Feather.
• ID spot 14 was used by the Snakeskin and Pretty Tail.
• ID spot 15 was used by the Water Tail.
• ID spot 16 was used by the Fire Tail.
• ID spot 17 was used by the Stimulus Orb.
• ID spot 18 was used by the Earth.
• ID spot 19 was used by the Calm Berry.
• ID spot 02 was used by the Full Restore.
• ID spot 05 was used by the Revive.

(Source: Pokémon Gold and Silver Disassembly)

Unused Held Items

In Generation II, Pokémon can have held items in the following ways:

• A Pokémon traded from Gen I via the Time Capsule will always have a held item, determined by the Pokémon's catch rate in their respective first generation game of origin.
• Some Pokémon in Generation II have a given chance to have a held item if encountered in the wild.

However, the following Pokémon cannot be encountered in the wild, so their held items go unused:

#	Pokémon	Held Item		Notes
		Common	Rare
149	Dragonite	(No Item)	Dragon Scale	Can't be found in the wild in either Generation, so this goes completely unused.
150	Mewtwo	(No Item)	Berserk Gene	Can only be obtained by trading from Gen I (where it will hold a BrightPowder instead) or by event, but never in the wild.
151	Mew	(No Item)	MiracleBerry	Can only be obtained legitimately in Gen II from event distributions (where it will hold a Bitter Berry instead).
172	Pichu	(No Item)	Berry	The only way to obtain this Pokémon is through breeding, as it never appears in wild battles.
173	Cleffa	MysteryBerry	Moon Stone	The only way to obtain this Pokémon is through breeding, as it never appears in wild battles.
238	Smoochum	Ice Berry	Ice Berry	The only way to obtain this Pokémon is through breeding, as it never appears in wild battles.
240	Magby	Burnt Berry	Burnt Berry	The only way to obtain this Pokémon is through breeding, as it never appears in wild battles.

Interestingly, it seems that at one point, Lugia was meant to hold an item, just like how Ho-Oh holds a Sacred Ash. Encounters can have a flag that forces a Pokémon to hold its held item, and this flag is set for both the Ho-Oh and Lugia fights, but Lugia has no held item defined so this does nothing.

(Source: Pokémon Gold and Silver Disassembly)