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.
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Aesthetic changes

    * 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.

Location changes

    * Elm's Lab has an upstairs level.
    * Maps have been remade to match the design style used in Diamond, Pearl, and Platinum.

Gameplay changes

    * 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 screen instead.

(from same source)