Boo (character)

Boos, known in Japan as Teresa (テレサ), are fictional ghosts from the Mario and Yoshi series of video games. They first appeared as a common enemy in 1988's Super Mario Bros. 3, in which they were called Boo Diddleys (a reference to the American rhythm and blues singer Bo Diddley). Since then, they have been a mainstay in the series, usually appearing as enemies, but occasionally appearing as playable characters in the Mario spin-off games, or even as allies of Mario, such as Lady Bow from Paper Mario and its sequel. They are named after the onomatopoeia of the sound that one might make when trying to frighten someone ("boo!"), whereas their Japanese name comes from the verb 'tereru' (照れる), meaning 'to be shy').

A Boo's most common pattern of attack is to sneak up on the player (usually Mario) from behind while they are facing away from them; however, they hide their faces (thus turning 'invisible') if looked at, hence the connotations of their Japanese name. Being ghosts, they are usually invincible, and unable to be defeated without certain items or conditions.

It has been implied that Boos may have been other living species before they became boos, but this has not been made clear. There are also sub-species of Boo based on other species; for example undead Shy Guys become "Boo Guys" while undead Lakitus become "Fishin' Boo"s.

Concept and creation
In an interview with Nintendo Power magazine, Mario franchise creator Shigeru Miyamoto stated that while working on Super Mario Bros. 3, co-designer Takashi Tezuka had the idea of putting his wife in the game. According to Miyamoto, "(Tezuka's) wife is very quiet normally, but one day she exploded, maddened by all the time he spent at work. In the game, there is now a character who shrinks when Mario looks at it, but when Mario turns away, it will grow large and menacing".

Boos appear as white, spherical, levitating ghosts, similar to the will-o'-the-wisp phenomenon or the Japanese Hitodama. They have faces featuring large fangs and long tongues, and three short extremities which resemble two arms and a tail. Being ghosts, Boos often appear in haunted house-themed levels in the games, in which they'll "sneak up" on the player, much in the fashion of ghosts of popular culture. Their presence can be recognized by their signature cackle. They are generally depicted as bashful and mischievous in nature.

Mario series
Boos first appeared (as "Boo Diddleys") in 1988's Super Mario Bros. 3 for the NES, appearing in the more difficult fortress levels in which they pester Mario or Luigi by sneaking up on them. Since their first appearance, apart from their names being shortened simply to "Boos", their design or habits have not changed significantly, despite their appearances is most games since Super Mario Bros. 3, however, they have spawned a number of subspecies over the years, the first being an enemy named 'Stretch' from Super Mario Bros. 3, essentially a Boo in the shape of a ghostly, white platform which will attack Mario or Luigi should they attempt to step on it.

Boos played a much more prominent role in 1990's Super Mario World, in which they were the starring enemies in the game's many 'Ghost House' levels. In these levels, Boos would attack in groups and in a number of creative attack patterns, such as flying in wide circles in order to create obstacles for the player, or swarming in order to increase their attack radius. Super Mario World also introduced the "Fishin' Boo", a ghostly version of a Lakitu, as well as the secret boss "Big Boo", a larger and tougher Boo who would return as a boss throughout the series. Super Mario World was also the first point in which it was revealed that some Boos were able to transform into blocks, which, if lured into a suitable position, can be used to reach otherwise unreachable platforms, a theme which would appear again in 2002's Super Mario Sunshine, as well as in Yoshi's Story of the Yoshi series.

In the 2001 Nintendo GameCube launch title, Luigi's Mansion, the Boos were given the role of primary villains, alongside the other miscellaneous ghosts of the mansion. The game's primary antagonist is King Boo, a large Boo wearing a crown who leads the Boos of the mansion, who is responsible from trapping Mario inside a portrait. It was this game that established Luigi's fear of ghosts, and particularly Boos, something which would become part of his character throughout the series. This encouraged the Boos to pick on Luigi in future games. For instance, they locked Luigi away in Super Mario 64 DS and trapped Luigi in a haunted mansion in Super Mario Galaxy. King Boo and his minions are also expected to play a prominent role in the upcoming sequel to Luigi's Mansion for the Nintendo 3DS, Luigi's Mansion: Dark Moon.

In 2007's Super Mario Galaxy and its sequel, Mario and Luigi are able to transform into Boos themselves, through the use of the "Boo Mushroom" (a version of the series' famous Super Mushroom). In this form, the player is able to levitate and pass through certain walls, as well as being able to understand the Boos' language; "Booish".

Boos also make frequent appearances in the Mario spin-off games, sometimes as enemies or as part of the scenery, but sometimes as playable characters, the first instance of this being a playable Boo in 2000's Mario Tennis for the Nintendo 64. Starting in 1996's Mario Kart 64, Boos have appeared as items in some of the Mario Kart games, in which their purpose is to steal items from other racers. King Boo appeared as a playable racer in Mario Kart: Double Dash!! and Mario Kart Wii. Boos re-appear in Super Mario 3D Land as well as New Super Mario Bros. 2, the latter introducing a new species called the Boohemoth.

The first instance of a friendly Boo who fought on Mario's side was Lady Bow from 2001's Paper Mario and its sequel.

Yoshi series
Being the sister series of the Mario games, Boos also appear in similar roles throughout the Yoshi series, making their first appearance in the 1991 puzzle game, Yoshi (known as Yoshi's Egg in Japan and as Mario & Yoshi in Europe and Australia), in which they appeared alongside Goombas, Piranha Plants and Bloopers as "blocks" which must be stacked in order to hatch a sizable Yoshi. They also appear as opponents in 1992's Yoshi's Cookie, as well as appearing as enemies in the 1993 first-person shooter Yoshi's Safari.

Boos have also appeared in a number of forms in all of Yoshi's main platform games, starting with Super Mario World 2: Yoshi's Island in 1995, in which they appear as common enemies, as well as having a boss in the form of 'Bigger Boo'. In the Yoshi games, Boos mainly act in the same way as they do in the Mario games.

Other appearances
Outside of the games, Boos also appear in the Super Mario-kun comics.

Boo may have been the inspiration for characters in other Nintendo series, such as "Mumbies" and "Scarfies" from the Kirby series, both of whom, like Boos, only attack Kirby when he is not facing them. There is also a character named "Wisp" from Nintendo's Animal Crossing series, a ghost who strongly resembles a Boo.

Reception
With Boo being one of the more popular Mario enemies, their image has been used in official Nintendo merchandise, such as plush dolls, as well as cookie cutters. IGN's Audrey Drake listed Boo as one of Mario's best enemies.

Celeste Monsour of Geek culture website Fandomania published a list of ten of her favorite Boo-related arts and crafts created by fans for Halloween.

The British Official Nintendo Magazine included the Boo Mushroom in their "Top 20 Mario Power-ups", ranking it at fourteenth, stating that it's "ruddy mint". Geekosystem also included the Boo Mushroom in their list of the "10 Greatest Mario Power-Ups", rating it 3rd in usefulness and 5th in whimsy, and 7th overall.