Egg Groups & Moves

This is a sub-page of Development:Pokémon Gold and Silver/Pokémon Data.

The information in this article is pulled from the following files in the JP and KR sources:

Egg Groups#

The earliest known egg group assignments can be found in the July 18th monster group. A few changes were made by August 17th, all but one of them being additions to existing egg groups. The lone exception is Sunkern, which had its egg group removed, further evidence that it was originally on the chopping block. These same egg group assignments stuck around until Spaceworld 1999.

After Spaceworld came a new swath of changes:

• Nidorino and Nidoking were moved from the Undiscovered egg group to the Field group.
• All baby Pokémon were put in the Undiscovered egg group, meaning they're no longer able to breed, thank goodness.
• Togetic was added to the Flying egg group.
• Marill and Azumarill had their second egg groups changed from Field to Fairy to better match the Pikachu line.
• Sunkern and Pineco were placed in the Grass egg group.

The last changes were done between August 23rd and August 30th:

• Nidoran♀ and the Nidoran♂ & Mareep lines were changed from being solely in the Monster or Field egg groups to being in both.
• Three Pokémon that were in the Mineral group moved to different groups: Shuckle shuffled off to Bug, the Slugma line went Amorphous, and Unown was put in Undiscovered.
  • Pineco, which had previously been relocated from Mineral to Grass, was moved one last time to the Bug egg group, as was its recently added evolved form Forretress.

Egg Moves#

Timeline#

1999/08/17#

The earliest known batch of egg moves is in the Spaceworld 1999 demo. Most Pokémon have 5 egg moves, though there are a few with 4 moves.

• Caterpie, Weedle, Magikarp, and Unown all have egg moves in this group. Three of those Pokémon have yet to gain access to any of these moves, while a Hydro Pump Magikarp was first distributed at a Japanese event in 2013.
  • Smeargle also had egg moves at one point, but since it could just Sketch any move anyway, it was no big loss when they were removed.
• Strangely, Bellossom, Steelix, and Porygon2 have egg moves despite being fully evolved Pokémon. The existence of these moves combined with entries for Tsubomitto, Madaamu, and Purakkusu, three Pokémon that had not only been cut by this point but were also fully evolved, suggests that the person who was assigning moves was working from an earlier list of Pokémon - one where they were all lacking evolution methods, thus appearing to be single stage Pokémon. Or it could just be a series of simple mistakes, which would explain how Octillery of all things got a set of egg moves...
• Whoever was assigning egg moves must have been confused, because they thought Magnemite, Voltorb, Porygon, and Unown could interact with Pokémon in the Mineral egg group despite being genderless. Geodude, Onix, Sudowoodo, Pineco, Shuckle, and Magcargo's egg moves were all chosen based on the assumption that the aforementioned Pokémon could pass down moves.
• Signature moves appear as egg moves much more often, even in cases where there was no valid parent to pass down the move:

:* Egg Bomb: Cleffa, Igglybuff, Togepi (no valid parents for any of them).

:* Bone Club: Farfetch'd (from Smeargle).

:* Kinesis: Drowzee (from Abra).

:* Softboiled: Exeggcute (no valid parent).

:* Glare: Meowth (from Ekans).

:* Lovely Kiss: Vulpix (from Smeargle), Mr. Mime (no valid parent).

:* Spore: Oddish, Bellsprout, Hoppip (from Paras).

:* Hyper Fang: Nidoran♀ (from Rattata).

:* Super Fang: Nidoran♂ (from Rattata).

:* Sketch: Drowzee (no valid parent).

(Sketch is move 165; this was probably supposed to be move 065, Submission, which Drowzee can learn by TM in Generation I. Machop would be able to pass that move down, since it and Drowzee are in the Human-Like egg group.)

• Grimer has Struggle as an egg move, which is baffling because the move only appears in battle after the PP of every other move has been depleted. There's no way to "learn" it, so it definitely can't be passed down.
• Hoothoot is the only Pokémon that already had its egg moves finalized.

1999/08/18#

At this point, all Pokémon have five egg moves.

• Smeargle's egg moves were deleted.
• The following moves were removed from all egg pools: Struggle, Sketch, Sacred Fire, Aeroblast.
• This is the earliest spreadsheet with egg move data. Each cell lists the move ID and the move's name, but there are a few instances where the ID and name don't match up, in which case the move ID takes priority. However, the named moves usually make more sense:

:* Abra: Agility should be Rapid Spin.

:* Geodude: Cross Chop should be Ancientpower.

:* Farfetch'd: Twister should be Tri Attack.

:* Mareep: Thunderpunch should be Bite; Earthquake should be Tail Whip.

:* Murkrow: Horn Drill should be Drill Peck.

:* Steelix: Agility should be Rapid Spin.

:* Magcargo: Agility should be Rapid Spin.

1999/08/22#

There was a mass cleanup of invalid egg groups and uncommon / inaccessible egg moves between the 18th and the 22nd.

• Caterpie, Weedle, Unown, Steelix, Octillery, and Porygon2 all had their egg moves deleted.
• As a side effect of the Pokémon getting shuffled around, Yanma and Shuckle temporarily lost their egg moves.
• After Aipom was put in Quagsire's old slot and Wooper was put in Aipom's slot, they inherited the other's egg moves, which is why Wooper has Thundershock and Aipom has Hydro Pump in this group. Rather than switching the egg move pools back, the developers started modifying the moves in the swapped pools instead.
• Pineco moves from Mineral to Grass, gaining a new set of egg moves in the process.
• The following moves were removed from all egg pools: Vicegrip, Bind, Sand Attack, Poison Sting, Ember, Water Gun, Poisonpowder, Earthquake, Teleport, Smokescreen, Withdraw, Sludge, Bone Club, Kinesis, Glare, Poison Gas, Spore, Hyper Fang, Super Fang, Powder Snow, Vital Throw, and Megahorn.
• Four more Pokémon got Milk Drink. Two of those Pokémon can inherit it from Smeargle, and the other two can't learn it at all.
• This set fixes some of the move ID / move name discrepancies but introduces a couple more. These can't be seen in the txt file, but are in the 擦得技VER1.3.xls spreadsheet:

:* Spearow: Twister should be Tri Attack.

:* Machop: Tail Whip should be Thunderpunch.

• There are also two other errors:

:* Ledyba: Faint Attack is listed twice.

:* Misdreavus: One of its egg move slots is completely blank.

1999/08/23#

• Magikarp's egg moves were deleted. R.I.P. Minimize Magikarp.
• Yanma and Shuckle get their egg moves back.
• Thundershock and Minimize no longer appear in egg move pools.
• One last move ID / move name inconsistency:

:* Misdreavus: The second Sludge Bomb should be Sludge.

• Six of the egg moves pruned by this point would later be distributed through Pokémon Eggs obtained at the defunct New York City Pokémon Center in 2002 and 2003:
  • Leech Seed Oddish
  • Synthesis Paras
  • False Swipe Machop
  • Confuse Ray Tentacool
  • Rapid Spin Geodude
  • Mind Reader Mr. Mime

1999/08/30#

From this group on, the number of egg moves per Pokémon was destandardized; Pokémon may now have as little as 1 and as many as 8 egg moves. The egg move spreadsheets were also changed to only include the move name in each cell, eliminating the move ID / name discrepancies from the earlier lists.

• Sunkern's egg moves were deleted. Someone on staff must have felt bad for it, because Sunkern got egg moves from Generation III onward.
• This is the first instance of Tyrogue having egg moves, all of which made it to the final game.
• The following moves were removed from all egg pools: Fire Punch, Thunderpunch, Horn Drill, Tail Whip, Recover, Egg Bomb, Milk Drink, and Spark.
• Shuckle was moved from the Mineral/Field egg group to the Bug egg group. As a result, Geodude and Sudowoodo lost access to Lock-On, and Onix lost access to Tri Attack.
• After Magcargo was moved from the Mineral group to the Amorphous group, all of its old egg moves were replaced by a single move, Acid Armor.

1999/09/12#

• Magnemite, Voltorb, Porygon, and Bellossom's egg moves were finally deleted. However, an Egg containing an Agility Magnemite was eventually distributed at the New York City Pokémon Center.
• Geodude, Onix, and Sudowoodo's invalid moves were all either replaced or deleted, leaving them with only one or two egg moves to their name.
• The following moves were removed from all egg pools: Bubble, Sharpen, Conversion, Lock-On, and Conversion 2.
• Most invalid and redundant egg moves were deleted by this point, though a few managed to make it into the final game.
• Staryu was made genderless at some point between September 9th and 10th, as stated in Document\ダケモン金銀\p20911.txt in the JP source. Its egg moves should have been deleted by this point, and the txt file says that they were, but they somehow made it all the way into the final game. It would take until Pokémon Crystal for them to get them properly pruned.

Removed Groups#

Legend

• Bold: Move difference between sets.
• Red: No valid parent to pass down move.
• Blue: Pokémon can already learn move through TM, making the entry redundant.

Egg Move Changes (001-151)#

Legend

• Bold: Move difference between sets.
• Red: No valid parent to pass down move.
• Blue: Pokémon can already learn move through TM, making the entry redundant.

Egg Move Changes (152-251)#

Legend

• Bold: Move difference between sets.
• Red: No valid parent to pass down move.
• Blue: Pokémon can already learn move through TM, making the entry redundant.