PokÃ mon Gold and Silver are two role-playing games made by Game Freak and published by Nintendo for the Game Boy Color handheld . They are the second games in the PokÃ mon series , and increased the number of PokÃ mon to 251 . PokÃ mon Gold Version and Silver Version are the second installments of the PokÃ mon series of role-playing video games developed by Game Freak and published by Nintendo for the Game Boy Color .