Mega is a new item to the MarioKart series.The Mega Mushroom will make you huge upon usage, any Vehicles you bump into will be squashed. You can also travel off-road without speed loss. It will also relieve you of getting squashed yourself (e.g. getting flattened by a car in Moonview Highway). Although it is impervious to most items, it will still be affected by Bullet Bills, anyone with a Star, and a Thunderbolt (the first two making you flip over like any normal racer, and the Thunderbolt making you return to your original size). It also cannot lift up a truck in Moonview Highway, but it will simply bump into the truck as if it were another Mega Mushroom user (or a teammate in Battle mode).
This item is typically obtained in the middle of the pack. 4th to 8th place
The Mega Mushroom is a newcomer to the Mario Kart series, it has only appeared in Mario Kart Wii.