Mega Mushroom
The Mega Mushroom is a rare variety of mushroom found in the Mushroom Kingdom. When eaten, they grow their consumer to a massive size. They first appeared in Mario Party 4, with a light green cap. They let the player hit two Dice Blocks at once, making the player grow huge and crush other players as they stomped across the board. Additionally, a Super Mega Mushroom was available, which did the same thing but with three Dice Blocks.
They recently reappeared in New Super Mario Bros., where they yet again made Mario grow to a humongous size. In this colossal form, Mario could stomp across the level and crush anything in his path - enemies, blocks, Warp Pipes... even the end of level flag! These mushrooms were rarely found, and almost always came from Mushroom Houses or Red Flying Blocks. Even though these are strong if you were to jump and land on a hole covered with bricks, you would fall in dying if the hole was big enough.