What power-up turns Mario into a giant in New Super Mario Bros.?

In New Super Mario Bros., the Mega Mushroom turns Mario into a giant. When collected, it temporarily transforms him into Mega Mario, a huge and highly destructive form that can smash enemies, blocks, pipes, and other scenery.

The power-up was introduced in the 2006 Nintendo DS game New Super Mario Bros. Its visual design resembles an oversized mushroom with a yellow cap and red spots, distinguishing it from the familiar Super Mushroom. While the Super Mushroom makes Mario larger and lets him break certain blocks, the Mega Mushroom creates a much more powerful transformation.

Mega Mario is also temporarily invulnerable to ordinary enemy contact. The player can charge through portions of a level, destroying objects and earning points for the damage caused. The effect ends after a short period, returning Mario to his previous state.

The Mega Mushroom is easy to confuse with the Super Mushroom because both enlarge Mario. The Super Mushroom is a standard defensive power-up found throughout the series; the Mega Mushroom is the short-lived giant form associated especially with New Super Mario Bros. and its later appearances.