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This area is not necessary to finish the game storyline, but it's important to fill the Pokédex. The Power Plant is a huge maze containing many kinds of items and Pokémon, including the winged mirage Zapdos.

The Power Plant is the home of many Electric-type Pokémon like Voltorb and Pikachu and, in the Yellow version, the Poison-type Pokémon Grimer and Muk also appear there. However, the most important Pokémon there is the winged mirage Zapdos, which lies at the end of the maze. Also, there are lots of rare items in there as Pokéballs, but some are actually Voltorbs or Electrodes.