Three years after the release of the original three Pokemon games, Nintendo introduced the second generation of games (often known as the metal generation): Pokemon Gold, Pokemon Silver and later Pokemon Crystal. These three games had improvements in graphics, sound, gameplay, and sheer size. 100 newly developed Pokemon were added into the already large mass of mysterious creatures. Not only that but these games set a standard for how to rethink an old idea and make it fresh and enjoyable once more.

The majority of the game takes place in the new region of Johto. Like its predecesors, the game featured a new young trainer whose goal was to travel around the countryside, collecting badges and new Pokemon alike in order to complete the PokeDex and become the ultimate Pokemon Master. Unlike the previous games, however, the young trainer does not gain his starter right away. Rather it is entrusted to the trainer after a job well done. Thus begins an adventure across two large regions, facing enemies and gaining allies along the way.

The "disbanded" Team Rocket is back to its old schemes again, in Pokemon Gold, Silver, and Crystal. Using the Goldenrod City Radio Tower as a pawn in their evil plan, they hope to use its broadcast to unwillingly evolve Pokemon before their time. It is up to you, the young hero, to face them wherever they go. Only by using your Pokemon wisely, and with a little help from the region's Champion Lance, are you able to overcome the masses of bad gang members and save all the Pokemon in Johto.

The gameplay in Pokemon Gold, Pokemon Silver, and Pokemon Crystal is leaps above its color brethen. The 2nd generation in the Pokemon franchise brought a Special split, seperating the first generation's "Special" stat into Special Attack and Special Defense. The games also introduced Pokemon with genders. One of the biggest draws to the game was the RTC, or real time clock, which allowed the game world to simulate the dream world, with only certain Pokemon appearing at certain times of day. Seven specialized Pokeballs were introduced and obtained through giving Kurt apricorns. The now cherised Shiny Pokemon were also created for the second generation. The reason why a shiny sprite "sparkles", even in todays games, were in case you were playing on a monochrome Game Boy.

Pokerus, the helpful virus, makes its debut in Pokemon Gold, Silver, and Crystal as well, doubling a Pokemon's stat experience (a predecesor to the effort value). The newly added Steel and Dark types were added to help bring balance with the Psychic type, whose Pokemon had dominated the Pokemon Red, Blue, and Yellow game much more than dragons. The ability to hold items such as Leftovers, and breed Pokemon in a day care center were also welcome additions. One of the most praised features in the game was the fact that after beating the Johto Elite 4, the trainer could return to the land of Kanto, albeit three years later from the original games where much has changed.

But probably the most important feature of the game was its backwards compatability with Pokemon Red, Blue, and Yellow. Through the use of a "time machine", a trainer was able to send Pokemon into the past from their Pokemon Gold, Silver, and Crystal games, and send Pokemon into the future from their Pokemon Red, Blue, and Yellow games. This feature didn't carry over to the third generation, which led to a lot of unhappy gamers. "Time", in many ways, is a key element in the metal generation. From sending Pokemon across time, to traveling a changed Kanto, to playing with a real time clock. Even its most secret legendary, Celebii, was a time traveler. It was these features and more that allowed the Pokemon franchise to live on for even more gamers.