Super Mushroom

A Super Mushroom is a red Mushroom that serves a particular function depending on the game in which it is found. Its first and most common effect is causing Mario or Luigi to double in size and strength, allowing them to smash through bricks and take an extra hit.

The idea for super mushrooms were originally believed to have been inspired by the cake that Alice eats in Alice in Wonderland that makes her grow after having been shrunk by a poison. However, Shigeru Miyamoto later corrected himself, saying that this was a misunderstanding; the mushrooms were actually inspired by the concept of mushrooms being associated with magical worlds in general, like the Wonderland of Alice in Wonderland and the Mushroom Kingdom.

Super Mario series
In Super Mario Bros., Super Mario Bros.: The Lost Levels, Super Mario Bros. 3, Super Mario World, New Super Mario Bros. and New Super Mario Bros. Wii, the Super Mushroom confers the Super status on Mario or Luigi.

In the first game it appears in, Super Mario Bros., the mushroom appears much differently than the icon it would later become. The mushroom lacked eyes and had a red/yellow color scheme rather than the modern red/white. It was also shaped more like an actual mushroom. These differences were more likely due to the graphical limitations of the time.

The next game they appear in is Super Mario Bros. 2 behind doors or inside vases. The have the same effect as in the first game, though function more like a typical life meter and can extend a player's hits to more the usual one.

Mario Party 7
In the Pearl Hunt sub-game, one of the obtainable items is a super mushroom, although it's golden. The real super mushroom is just called "Mushroom". Due to how Pearl Hunt works, the super mushroom gives you two extra tries.

Super Mario 64 DS
In Super Mario 64 DS, the Super Mushroom works more similarly to the effect of the Mega Mushroom in that it increases the player to a size large enough to destroy most things in their path. If any enemies were defeated after seven, a bonus 1-Up would be received.

Donkey Kong series
Super Mushrooms also made an appearance in Donkey Kong for the Game Boy. They were used by Donkey Kong during the final battle. He ended up using several of them to transform himself into a giant. A Super Mushroom was also briefly seen in the ending when Pauline gave one to Mario, so that he could change his size and catch Donkey Kong when he was falling.

Hotel Mario
The Super Mushroom appears in Hotel Mario. It doesn't make Mario big or small, but gives him the chance to take one hit and not lose a life. The only difference between the normal Mario and the one that ate the Super Mushroom is the color of his overalls.

Mario Kart series
In relation to Mario Kart, a Super Mushroom is an item that grants a Kart a brief burst of speed when used. Super Mushrooms can come in singles or triplets, the latter providing three Mushrooms to use in a row. In Mario Kart: Double Dash!! a character holds these mushrooms in piles, but if the kart is hit by an item on the road, these mushrooms will fall off and the character will have one reaimining on hand. Normally this set appears as default power-ups in time trial mode (excluding Super Mario Kart) to use specially over shortcuts of a determined course. Another type of Super Mushroom is the Golden Mushroom, that can be used indefinitely in a restricted period of time.

In recent Mario Kart games, Super Mushrooms can be used as well to knock aside other karts or even steal an item from the opponents when coming in contact as seen in Double Dash!!. In later games, this move is not possible to steal items, but works to steal balloons, Shine Sprites or Coins from other players when playing in Mario battle mode.

Super Smash Bros. series
In Super Smash Bros. Melee, the Super Mushroom allows the player to grow to an incredible size, thus making him/her heavier and harder to knock off. Experiment with them in Huge Melee mode. Use one while playing as Mario, then do his taunt. This will make him taller than almost all the levels in the game.

In Super Smash Bros. Brawl, the Super Mushroom had an additional effect. Not only are the fighter's size and weight increased, but his/her attack strength also increases. An attack that normally does 15% damage could do near 30% damage when the fighter is a giant.

Trivia

 * The manual of the original Super Mario Bros. actually refers to the Super Mushroom as the "Magic Mushroom", but the name was changed due to the accidental reference of hallucinogenic mushrooms.
 * The Super Mushrooms in the Super Smash Bros. series look exactly like the ordinary mushrooms used in the most recent Mario games.