For a long time before the announcement of Pokémon HeartGold and SoulSilver Versions, it was believed by many that remakes of Pokémon Gold and Silver would be produced and released during Generation IV on the Nintendo DS.
The possibility of these remakes took their precedent from the release of Pokémon FireRed and LeafGreen, Generation III versions of the Generation I Pokémon Red and Green, which were released in 2004. Based upon FireRed and LeafGreen being nearly exactly the same as Red and Green as far as storyline goes, the assumed storyline of the remakes would thus follow Gold and Silver very closely, with the player starting in New Bark Town and traveling across Johto, and later Kanto. Though disputed for a long time, these suspicions were finally confirmed with the announcement of the remakes themselves in May of 2009.
SOME HINTSGeneration III
Shortly after the release of the remakes of Generation I's paired versions in 2004, some fans began to expect a second pair of remakes, this time of the Generation II games, as, like Red, Green, Blue, and Yellow, Pokémon Gold, Silver, and Crystal were incompatible with the then-current Generation III. Unsubstantiated rumors and theories began to spread around forums online, and some fans went as far as to make hacks of Generation III games to "remake" Gold and Silver. On April Fool's day, 2004, Pkmn.Net showed faked screenshots depicting the Daycare on Route 34 in a remake, claiming that the screenshots came from CoroCoro.
Those who wished for remakes also pointed to allusions to Gold and Silver in Generation III's five games. For instance, Giovanni is revealed by a Rocket Scientist in the Sevii Islands to have a red-haired child, widely speculated to be the Generation II rival, Silver, while Bill's information in the Fame Checker mentions his hometown of Goldenrod City.
Notably, however, FireRed and LeafGreen were used to provide many Generation II Pokémon to Generation III games, as most were missing from the Hoenn Dex (and thus not available without trading in Pokémon Ruby and Sapphire), while the only Generation III Pokémon available were Azurill and Wynaut, themselves breedable from Generation II's Marill and Wobbuffet. An NPC even gives away a Togepi egg, as Elm does in Generation II, and aside from Pokémon Colosseum and Pokémon XD, this is the only way to get many of these species.
Despite the theories of the many, the time of the Game Boy Advance passed, and Generation III ended without a remake. With Generation IV and the Nintendo DS, however, those who were not discouraged transferred their theories, speculating for a remake that would be released some time after Pokémon Diamond and Pearl. Like in Generation III, several mentions are made during the course of Sinnoh's games, some more obvious than others, of events and locations in Generation II. Examples of this include a news report of the red Gyarados, Jasmine's appearance in Sunyshore City, an explicit mention of Professor Elm and his report about eggs, Cynthia's SecretPotion (which mentions Cianwood City in its bag description, as it did in Generation II), Bebe's friend from Johto who has many Eevee (possibly Bill considering their similar line of work), and the man in the Hotel Grand Lake who mentions Ho-Oh's roost of the Tin Tower and Lugia's home of the Whirl Islands and the fact that Clefairy dance on Monday night in Mt. Moon.
The only concrete clue, however, was hidden, in-game data for the locations displayed on a Pokémon's status screen. While a Pokémon caught in Sinnoh will display the area it was caught in, and Pokémon sent from Generation III via Pal Park display "Hoenn" or "Kanto", depending on the game in which they were originally caught, the data also includes "Johto", at the time inaccessible through any means.
Alongside the more concrete references listed above, there are a few "hints" theorists have pointed out that are far more speculative. Some examples follow:
The Park Balls are gold and silver in color, with a light blue band across their middle. This may represent Gold, Silver, and Crystal.
Like in Gold and Silver, the rival of Diamond and Pearl can be battled twice a week on certain days after the final static battle with him.
Gold and Silver introduced two new Eevee evolutions, Espeon and Umbreon, and a Porygon evolution, Porygon2; likewise, Generation IV introduced Glaceon, Leafeon and Porygon-Z.
Sweet Honey, an item in Sinnoh that can catch Pokémon in certain trees, was initially a concept meant to be included in Gold and Silver, but replaced with Headbutt.
In Pokémon Platinum, the legendary birds were found roaming Sinnoh after the player has beaten the Elite Four. As a result, the legendary beasts are currently the only legendary trio not available through a Generation IV game, and could be supplied by a remake.
It should be noted that Gold and Silver never explained what became of the legendary birds. Players were left to assume that the birds fled after their respective "nests" were disturbed by Red three years earlier, or were caught by the same. As Generations II and IV are concurrent, we can now assume that the trio fled to the Sinnoh region, and therefore, their absence could be better maintained in a remade Gold and Silver.
When presented with Oak's Letter, Professor Oak states that the white rock on Route 224 in Sinnoh has a counterpart in Kanto. There has been no appearance of a white rock in the Kanto region, though a smaller white rock is seen in Mossdeep City in Ruby, Sapphire, and Emerald. Kanto's white rock could be a Generation IV addition that would appear in a remake leading to the Shaymin event (much as Pokémon Emerald included Navel Rock and Birth Island to capture Ho-Oh, Lugia, and Deoxys).
There are unused sprites for Shellos and Gastrodon in Pokémon Diamond and Pearl; since their Pokédex data say that their colors and shapes differ from region to region, it's possible that their unused forms are meant to be obtained from Johto via Gold and Silver remakes.
The Pokédex data also mentions that Mantyke's special patterns also differ from region to region. Since this is its generation debut, it could be possible to see alternate sprites as well (though admittedly, while Arbok's sprites changed from the Generation I games to Generation II games, Generation II does not have 2 sprites: one pattern for Kanto, and another for Johto. Also, Sinnoh's and Kanto's sprites have the same pattern, while Johto's and Hoenn's are similar).
The Poké Ball motifs on the floors of the Pokémon Centers are gold on the top half and silver on the bottom half. This design also appears in Pal Park.
During a wild Pokémon battle, if the bottom screen is tapped with the DS stylus at certain times before and after the battle options appear, the normally red and white Poké Ball becomes gold and silver colored.
Ragecandybars are sold out at the shop on Boon Island in FireRed and LeafGreen and at the Department Store in Veilstone City in Platinum, hinting at their inclusion in a possible remake.
When going through the Distortion World for the first time, players must complete a puzzle that involves moving boulders with the move Strength to reach Giratina. This puzzle is similar to the puzzle in the Blackthorn Gym.
Eusine from Pokémon Crystal and Looker from Pokémon Platinum have some similarities. Both are introduced in the third game of their respective generation to enhance the game's plot. Each of them also have their own theme music.
Pokémon HeartGold Version (Japanese: ポケットモンスター ハートゴールド Pocket Monsters Heartgold) and Pokémon SoulSilver Version (Japanese: ポケットモンスター ソウルシルバー Pocket Monsters Soulsilver) are paired Generation IV remakes of the Generation II games Pokémon Gold and Silver.
Much like Pokémon FireRed and LeafGreen revisited the Generation I story of Kanto, HeartGold and SoulSilver will revisit the story of Johto, with the player's starting area being New Bark Town. As there are no definitive details about the games yet, it is currently unknown whether or not changes to the plot and course of the original games will be made. What is currently known, however, is that the geography of New Bark Town, while updated, has not changed. The player's rival, Silver, lurks outside of Professor Elm's lab as he did in Generation II.
Like FireRed and LeafGreen, it is assumed that several enhancements will be made to the games to bring them up to speed with Generation IV, including adding features and Pokémon introduced in Generations III and IV. It has also been confirmed that brand new features, never before seen in the series, will be introduced. As indicated by data in Diamond, Pearl, and Platinum, these games are highly likely to be compatible with the Sinnoh three for battling and trading, though like FireRed and LeafGreen, certain objectives might need to be accomplished beforehand.
Kris, despite being the female counterpart of Crystal's player character Gold, is believed not to be included as the female counterpart, with a new character instead taking her place.
Changes from Pokémon Gold and Silver
Gold received a redesign while a new player character apparently replaces Kris.
The DS's 3D capabilities are utilized in selecting the starter Pokémon.
The PokéGear has been redesigned. Now, it features two designs, one blue and white for males and another white and pink for females.
An image of certain locations, similar to that of FireRed and LeafGreen, appears when entering the location.
Elm's Lab has an upstairs level.
Maps have been remade to match the design style used in Diamond, Pearl, and Platinum.
The player's starter will follow them, similar to Pikachu in Yellow. More specific details are currently unknown.
Similarly to the event Shaymin and Regigigas's effect on Platinum, the Pikachu-colored Pichu to be given to those who have pre-ordered tickets to the twelfth movie will unlock an event near the Ilex Forest Shrine featuring the Notched-ear Pichu.
The screen that pops up when pressing the Start or X buttons in the previous games appears on the touch instead.
~EDIT by Smitie: Merged the two HG&SS threads