Power Balloon

The P-Balloon is an item that debuted in Super Mario World and appears quite rarely throughout the entire Mario series. It has the appearance of a yellow balloon with a large white "P" printed on it (possibly meaning "power", and presumably relating it to the P-Switch and the P-Wing). It resides inside Item Boxes and, when it is released, will float in a direction until it is picked up by Mario or Luigi.

The P-Balloon can be found in four levels:

Donut Secret 1

Donut Secret 2

Forest of Illusion 1

Tubular

The item's effect is to make whoever picks it up swell up like a balloon and become Balloon Mario or Balloon Luigi, causing them to hover in the air. They will gradually float upwards if not moved by the player, but are capable of moving in any direction for a limited amount of time. During this time, Yoshi cannot be ridden. Mario or Luigi will start to flash when the item is about to wear off, and when it does they return to normal size and drop out of the air. The level Tubular in the Special World requires the player to continually pick up new P-Balloons to maintain flight while they make their way across the level. If Mario or Luigi pass through a Giant Gate while under the effects of the P-Balloon, they will gain a bonus Super Mushroom.

While the P-Balloon item has been rarely seen after Super Mario World, its effects lived on in Super Mario 64 DS where, on picking up a Power Flower, Mario would blow up just as with the P-Balloon and float. The control scheme for this transformation has been changed somewhat; Mario now gradually floats downwards instead of upwards, and has to be kept in the air by tapping the jump button, similar to swimming in 2-D Mario games. Once again, he flashes when it is about to wear off and plummets when it does. Mario is the only character who is affected this way when he picks up the Power Flower. Later, in Mario & Luigi: Bowser's Inside Story, Mario can become Balloon Mario after being air-inflated. Luigi can grab onto Mario, so they can jump up and slowly float down.

The P-Balloon also made appearances in the Super Mario World television series, most notably in the episode "Mama Luigi" where Luigi uses it to float safely down a chasm. Later in the episode, Mario uses it to re-inflate Luigi back to his normal shape after he was flattened. In the series, the P-Balloon is referred to as a Magic Balloon. It also appears in another episode, "Gopher Bash".

Trivia

 * When Yoshi uses a Blimp Fruit in Super Mario Galaxy 2 and becomes Blimp Yoshi, he swells up as if he used a P-Balloon.
 * Puffy Wario has a similar effect based on the P-Balloon, but Wario has to be hit by certain spiked enemies to inflate his head, and he can only float upwards until he hits the ceiling.
 * If Mario/Luigi has the powers of a Super Mushroom, Fire Flower or Cape Feather, and grabs a P-Balloon, he will still have whatever powers he originally had as well as those of the P-Balloon. However, if he collects any of these items while under the effects of a P-Balloon, the P-Balloon's power will instantly wear off.
 * In Super Mario World: Super Mario Advance 2, when Mario or Luigi grab a P-Balloon, the music slightly goes slower than usual.