P Balloon

P-Balloons are power-ups in the Super Mario Bros. series, first appearing in Super Mario World. When collected, the power-up would make the player inflate like a balloon for some period of time, allowing the player to float around in the air. This power-up notably appeared in Super Mario 64 DS without the actual balloon, instead being used by Mario when using the Power Flower.

Super Mario 64 Manifestation
P-Balloons can reportedly be found in some personalized copies of Super Mario 64, typically functioning in a similar fashion to it's appearance in Super Mario 64 DS, though it reportedly can be found with it's own power-up without a Power Flower if the Power Flower does not manifest in the copy. Notably, some players have reported that it appears as it's own object resembling the P-Balloon from Super Mario World. Due to the power-up first appearing in Super Mario World and typically appearing with the same design, some have suggested the P-Balloon is a remnant from Super Mario FX.

Unused SM64DS Texture
Found in the files of Super Mario 64 DS is an unused red ball with the letter P written on it. This object potentially could be for a P-Balloon object before the power-up was made Mario's Power Flower ability. However, other people have suggested it was a placeholder texture for the Power Flower.