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The title of this article is conjectural; an official name for the article's subject has not been found, so it has been given a fitting title by the editors. If an official name appears that is not from the English Super Mario Bros. Encyclopedia, it is requested that the article should be moved to the correct name.

This article is about the submersible In Mario Kart 8 and Mario Kart 8 Deluxe. For the transformation of Yoshis after touching a Morph Bubble, see Submarine Yoshi.
Not to be confused with Subwarine.
The submarine stamp from Mario Kart 8

A submarine is an obstacle used in Mario Kart 8 and Mario Kart 8 Deluxe. They appear in Water Park in the Sub Coaster attraction, where they are controlled by Nokis. Touching one of them causes the player to receive a Spin Boost.