Fishing Boo

Fishing Boos (alternatively Fishin' Boos) are ghosts resembling Fishin' Lakitus that ride a cloud without a face.

Super Mario World
Fishin' Boos debut in Super Mario World. They carry a fishing rod and ride a Lakitu's Cloud, much like their Koopa counterpart. However, instead of a 1-Up Mushroom, Fishin' Boos carry a blue flame and follow the player in a way that makes it hard for them to Jump. Their clouds also do not have faces. They have the same immunities as a normal Boo and therefore can only be spin jumped on.

Super Mario Run
Since the version 3.0.4 update, Fishing Boos reappear in Super Mario Run, where they are found in the level Fishing Boo Taunts You. Although they are still found carrying harmful blue flames, they can also carry items such as Super Mushrooms, Coins, Color coins, and Super Stars. In this game, despite the flames they carry, the enemies themselves are completely inoffensive, and can be defeated with a stomp attack, which reveals that they are appear to be wearing sheets and have brown shoes.

Nintendo Puzzle Collection
A Fishing Boo makes another appearance in the Nintendo Puzzle Collection version of Yoshi's Cookie, where they appear as the fourth opponent in the game's VS. Mode if the player plays on the Hard difficulty.

Super Princess Peach
Fishing Boos also make an appearance in Super Princess Peach, and a calmer variety called C. Fishing Boo also appears. Both types reside in Shriek Mansion on Vibe Island, and only Rage can defeat them.

Super Mario Run

 * Notebook bio: "A ghost that rides a cloud looking for a good fishin' spot. They dangle items from their rods."

Trivia

 * Fishing Boos were also likely slated to appear in New Super Mario Bros. Wii, as an unknown object was named similar to Fishing Boo, but the idea was scrapped.