Mystery Zone
The Mystery Zone (Japanese: なぞのばしょ Mystery Place) is an area in Pokémon Diamond and Pearl that essentially serves as "filler space" between normally accessible areas. It exists all around Sinnoh, presumably to facilitate the precise entrance into the Underground, which has tunnels that travel where no routes and cities exist. There are no Pokémon in it; it is, for the most part, made up of trees and water. The menu cannot open while in the area, but the registered key item can be used. The background music in the Mystery Zone is a slightly different arrangement of the music on routes 206, 207, and 208.
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The player standing on water in the Mystery Zone.