The original type matchups in Pokémon Red, Blue, and Yellow were severely flawed. Because of the Ghost-type vs. Psychic-type conflict, the Psychic Pokémon were left with only one weakness, Bug-type. At the time there were very few Bug-type attacks, and the existing ones were too weak to be effective in high-level tournaments. As a result, Pokémon such as Alakazam, Mewtwo and Mew ruled the tournament scene. The game creators balanced out the type system in Pokémon Gold and Silver. With this installment, Psychic-types were made weak to Ghost-type attacks, and stronger Bug-type attacks (such as Megahorn with 120 power) and Pokémon (such as Heracross) were added. The creators also added the Dark-type, which is super-effective against Psychic-types and immune to Psychic-type attacks, and the Steel-type, which is resistant to Psychic-type attacks. These changes led to a more balanced game with a steeper learning curve.
