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The Blue Pipe is a pipe item found in Mario Pinball Land. These items can help Mario from losing a life or from leaving the area Mario is supposed to be. They usually appear when the player ventures into a new area as they appear between the flippers the player controls. It can be obtained by buying it from Toad, or hitting a ? Block.
Blue Pipes first appear in Super Mario Bros.. In Paper Mario, they are found in the Toad Town Tunnels in which they can lead to Goomba Village, Koopa Village, Dry Dry Outpost, Boo's Mansion, and Lavalava Island in an instant. They return in the sequel where they appear in the Rogueport Sewers to serve as shortcuts to Petalburg, Boggly Woods, Keelhaul Key, and Poshley Heights. There is also a differently colored blue pipe that leads to Fahr Outpost. They also appear in Super Paper Mario, where they are built by Welderberg. There are three in the game: One leads to Flipside's B2F, one to Flopside's B2F, and one to Flopside from Flipside (and vice versa). Each is accessible on the second floor of both cities.