Many people remember the first generation of Pokemon. Hell, it was the generation in the middle of a gigantic fad in the late-90's. Unfortunately, not many people remember the second generation of Pokemon as much as they did the first. That's fine; not every video game series is expected to be like the Mega Man series, coming out strong with a sequel. However, Pokemon Gold/Silver/Crystal picks up where the first left off, with a branch of the story line extending into Johto.
This is a part of the charm for GSC: a continuation of the previous story line, set in a quaint region of Johto. The stark contrast between Johto and the more boisterous, vibrant region of Kanto is a nice comparison for the game. It is also nice from a standpoint of time, as you get to see Kanto three years later (in Pokemon canon).
Pokemon GSC also introduces two new types into the game: Steel and Dark. Both have two types that they are super-effective against and two weaknesses. The Steel type, which is physical in this series, offers numerous resistances, but only offers three moves altogether in this generation. The Dark type, which is special in this series, offers a wider variety of moves, but less power. Both offset the power of the Psychic type, which dominated the landscape of the original Pokemon series.
The battle system is nice, splitting the Special stat into two: Special Attack and Special Defense. Some fighters benefit from this split, while others wallow in the change in format. This is a part of what makes the game great, as it makes you consider which pokemon to use for your team. Granted, the physical/special adjustment doesn't come until a couple generations later. However, the split is enough to ensure a more cerebral game experience. This generation also worked out numerous glitches, both in game and in the battle system. The original pokemon generation (Red, Yellow, and Blue) was ripe with glitches, from obtaining MissingNo to catching Mew without attending a special event.
There are some flaws with this series, namely the branding of which types are physical and special. Physical types cause damage based on their attack stat, hindering the likes of Sneasal, who can't use moves like Faint Attack and Ice Punch with impunity. Special types cause damage based on their special stat, which hurts pokemon like Gengar, who can't use Shadow Ball and Sludge Bomb effectively. This waters down certain pokemon's effectiveness, but it also raises the effectiveness of certain pokemon, too (see Alakazam).
Another problem with this series is the lack of a true villainous organization. Yes, there is your rival, who happens to be a shady character (and Giovanni's son). Yes, Team Rocket is the big bad group in this series. However, Team Rocket doesn't do much to stand out in terms of evil bidding. They don't try to take everybody's pokemon away just to be the only person with pokemon (i.e. generation five, Pokemon Black and White) or wants to start a new, perfect civilization, wiping out the current one (i.e. generation six, Pokemon X & Y). No, Team Rocket just gives a bunch of Gyarados killer migraines and takes over a radio tower. That just seems weak.
Still, don't let these detriments deter you from playing this wonderful series. Pokemon GSC has plenty to offer, including an improved battle system, a nice story line, and consistency throughout the series.
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