From the Super Mario Wiki
The Poltergust 4000 is one of Luigi's karts from Mario Kart DS. The kart's appearance resembles an upgraded model of the Poltergust 3000 from Luigi's Mansion. It has good speed, acceleration and handling but low weight, drift and items. Its speed is tied with that of the Gold Mantis. The pre-release version of the Poltergust 4000 had Professor E. Gadd's emblem on it.
The kart is unlocked for Yoshi and Waluigi as well when the player gets gold trophies in all Nitro or Retro Courses in 150cc, and becomes available for everyone else when gold trophies are obtained in every cup in Mirror Mode.
The Poltergust 4000 returns in Mario Kart Tour, where it is classified as a Super kart. Slipstreaming lasts longer and yields more points when using this kart. It uses the Standard tires. The game also introduces an icy-blue variant, named the Ice-blue Poltergust, which is classified as a tour-exclusive High-End kart.
Mario Kart DS
Mario Kart Tour
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