Dash Mushroom

The Dash Mushroom, commonly called simply the Mushroom, is a type of mushroom physically identical to a Super Mushroom that is used for speed boosts. It first appears in Super Mario Kart, and is a recurring feature in the Mario Kart series. The Dash Mushroom has also appeared in a few Mario & Sonic installments, its first being Mario & Sonic at the Olympic Games for the Wii.

Mario & Sonic at the Olympic Games (Wii)
In the Wii version of Mario & Sonic at the Olympic Games, Mushrooms are an item in Dream Platform, where they give its user a five second speed boost upon being used.

Mario & Sonic at the Olympic Games (Nintendo DS)
In the Nintendo DS version of Mario & Sonic at the Olympic Games, Mushrooms appear in the Dream Race event, where they give a character a short speed boost when used.

Mario & Sonic at the Olympic Winter Games (Nintendo DS)
Dash Mushrooms appear as items in the Supersonic Downhill Dream Event in the Nintendo DS version of Mario & Sonic at the Olympic Winter Games. They appear randomly scattered throughout the course, and allow the player to perform a Mushroom Dash by pressing the B Button, which gives them a boost of speed. The player can store up to five Mushrooms at once.

Super Smash Bros. for Nintendo 3DS / Super Smash Bros. for Wii U
In Super Smash Bros. for Nintendo 3DS and Super Smash Bros. for Wii U, the Dash Mushroom is a type of speed-based equipment that can only be used by Bowser, Bowser Jr., and Donkey Kong. Its common variant is simply referred to as a Dash Mushroom, while its uncommon variant is known as the Double Dash Mushroom and its rare variant is known as the Turbo Dash Mushroom.