Pokémon Gold Version[a] and Pokémon Silver Version[b] are 1999 role-playing video games developed by Game Freak and published by Nintendo for the Game Boy Color. They are the first installments in the second generation of the Pokémon video game series. They were released in Japan in 1999, Australia and North America in 2000, and Europe in 2001. Pokémon Crystal, an enhanced version, was released roughly a year later in each region. In 2009, on the 10th anniversary of Gold and Silver, remakes titled Pokémon HeartGold and SoulSilver were released for the Nintendo DS.