9-Volt

Wario is a major human character in the WarioWare series. He is a Nintendo fan, he collects everything about this company, and loves to play video games. 9-Volt lives with his mother, 5-Volt, and his pet Fronk in their house in Diamond City and attends Diamond City Elementary. He debuts in WarioWare, Inc.: Mega Microgame$! as one of Wario's friends who helps him produce microgames.

Since WarioWare: Twisted!, 9-Volt always stars together with 18-Volt, who becomes one of his best friends in the series.

Firstly, 9-Volt could be seen in the intro of WarioWare, Inc.: Mega Microgame$!, where he is called by Wario to join his "company" WarioWare, Inc. and to produce microgames for his upcoming game. Like Wario's other friends in Diamond City, 9-Volt agrees.

In 9-Volt's own story, the school is out and he skates home with his high-tech skateboard, SK8.
 At the house, 9-Volt gets into his room and plays with his mixing
console. 9-Volt says "Hello" a few times and with the help of the
machine he imitates the voice of Jimmy T. or at least a similar voice while saying it. 9-Volt's oversized Game Boy
 answers him with "OK". Then 9-Volt makes music with the mixing console
and spins records on it. Some kind of grabber comes out of the Game Boy
and pops an over-sized cartridge into it.

Later, while 9-Volt still spins records, Ken the Reporter appears and announces that the Game Boy Advance SP
 is on sale in stores. Quickly, he leaves the house and his skateboard
transforms into a hoverboard. With that, 9-Volt hurries to the next
store to purchase the new handheld.

9-Volt also makes a short appearance in the ending story of the
game, where Wario states to his employees in the WarioWare headquarters
that they wouldn't get anything of the money he earns with the game he
and his friends make and then he escapes. 9-Volt is in shock, but like
the other employees except for Mona, he didn't chase after Wario.

9-Volt is featured in four unlockable minigames in WarioWare, Inc.: Mega Microgame$!. In Skating Board,
 he appears as the protagonist of the game and has to avoid obstacles
and red birds with his skateboard. In the two-player minigame VS Chicken
 Race, 9-Volt is the character of the player who has to use the L Button, while the other player's character is a Fronk, possibly his pet. 9-Volt also makes an appearance in the minigame taken from Mario Paint, Fly Swatter, where the Spiny appearing in the congratulations sequence has been replaced by him. The minigame Paper Plane features 9-Volt as one of the characters looking through a window and telling the current flight time.

In WarioWare, Inc.: Mega Party Game$!, 9-Volt hosts a television show called Super Show. There, he uses a mixing console again and a Game Boy Advance with arms and legs that states "OK" in a similar way to the Game Boy in the prior game. After 9-Volt's entrance, Kat and Ana followed.

9-Volt is one of the ten selectable characters in the multiplayer games.

In the intro of WarioWare: Twisted!, 9-Volt comes along with Mona to Dr. Crygor's Lab. There, Dr. Crygor
 tries to fix Wario's broken Game Boy Advance with his invention, the
Gravitator. But it has no buttons anymore after the repairing, instead
of that the player has to move the system to move the character in the
game. 9-Volt and Mona try it out and enjoy it. Wario gets the idea to
make a new WarioWare game involving this style of gameplay.

9-Volt is shown to be a troublemaker at school in this game. In
his own story, a new student named 18-Volt came into his class. On his
first day at Diamond City Elementary, the teacher asks 18-Volt what his
hobby is, to which he responds by taking out his boom box and playing
loud Rock 'n Roll music.

18-Volt got in trouble for this and after school he heads for his
 house broken-hearted. However, 9-Volt stops him and states that he
enjoys his music. The two of them become fast friends and 9-Volt invites
 18-Volt over to his house. When they got there, 18-Volt is ecstatic to
see that 9-Volt has a Nintendo Entertainment System and the duo spends a lot of time on playing on the system. Eventually, his mother, 5-Volt tells 9-Volt to go to bed and 18-Volt to go back home.

At night, when 9-Volt has to sleep, he furtively plays with his
Game Boy Advance SP under the bedspread, but 5-Volt catches him in the
act and tells him to put it away.

In WarioWare: Touched!, 9-Volt and 18-Volt go to the Toy Express to get a copy of the coveted, new Nintendo GameCube game, 36-Volt Man.
 9-Volt snatches one and shows it happily to 18-Volt, who is carrying
his boom box on his shoulder. Curious about their new game, the two
friends quickly return to 9-Volt's House, in which he uses his SK8 to
reach it. On their way, they pass the alien Orbulon who is running after his flying spaceship.

At the house, 9-Volt and 18-Volt play far into the night and
reign victorious in the game. To celebrate their success, 9-Volt spins
records again, with 18-Volt dancing behind him and his Nintendo consoles
 in front of him. 9-Volt's mixing console features moving Mario and Luigi figurines, but it got so late that the two gamers fall asleep.

In the morning, when they wake up, it's already 9 o' clock.
9-Volt and 18-Volt are shocked about the fact that they're late and rush
 to school.

9-Volt is visited by 18-Volt again in WarioWare: Smooth Moves. There, he showed a Game & Watch handheld console to his tall friend and plays with it. 18-Volt mistakes it for a Nintendo DS Lite
 at first. He wants to see more of the console and gropes it, but 9-Volt
 still has the console in his hands and informs him that he is still
playing, but he couldn't wait and the Game & Watch breaks in two
halves. He gets furious and commands 18-Volt to get out of his house.

Now, 18-Volt has a bad conscience and tries to find a new Game
& Watch for his friend. He first looks in Toy Express, but they
didn't have what he desires. After leaving the store, 18-Volt notices
another store where some gamers lineup. He got into the store and the
owner of the shop, Shop Manager Iwata,
 coincidentally has the searched Game & Watch on offer. 18-Volt
reaches for it, but surprisingly 9-Volt does the same. The friends face
each other and they both excuse each other for their mistakes. 9-Volt
tells 18-Volt that he wants to always be his P2 and all goes
well after that.

n WarioWare: D.I.Y., a game called Super 9-Volt shows up in 9-Volt's stage. It's a spoof of Super Mario Bros. and stars 9-Volt rather than Mario. 9-Volt, skateboarding, hits a Question Block shaped like a Famicom cartridge every time a microgame is won.

9-Volt, along with Mona, Jimmy T., Orbulon, and Ashley apparently left WarioWare, Inc. to work for Diamond Software
 in this game. Although, the reason they switch companies is unknown,
various residents of Diamond City consider possibilities in the D.I.Y. Forums feature of the game.

18-Volt, who continues working for Wario, appears to view 9-Volt
as a rival after his departure, as suggested by his role as a boss in
his game and his greeting to the player where he insists that he works at "twice
 the power as that other guy you might be thinking of".

9-Volt appears in the Wii U game, Game & Wario. He hosts the minigame "Gamer", that stars him with his Game Boy Micro-like console, playing microgames. As he was supposed to sleep, 5-Volt
 often drops by his bedroom. If 5-Volt finds out 9-Volt is playing
video-games during his bedtime, he is scolded by her and the player
loses. On his minigame's title screen, 9-Volt is depicted as having red
hair; this is also the first time he is seen without his helmet.

9-Volt is also in the Bowling minigame, depicted on a bowling pin like most other characters in the game.

As with the other WarioWare characters, 9-Volt makes an appearance in Miiverse Sketch Masterpiece Collection,
 a series of video showcasing pictures of often questionable quality
made in the game's Miiverse Sketch mode. 9-Volt is the host of the
fourteenth video, themed after drawings of Samus Aran.

9-Volt makes a reappearance in WarioWare Gold for Nintendo 3DS.
 He, like the other characters, has a changed appearance, namely that he
 has grown a bit, has had his boxing gloves changed back to fingered
ones, and has more hair. His voice clips also no longer appear to be
filtered. He is also seen attending a school. In his story, 9-Volt
appears to find math uninteresting, but suddenly, Fronk
 appears despite not allowing pets in school to help 9-Volt make math
fun by connecting them to video games. 9-Volt also makes a cameo
appearance as a DJ in 18-Volt's opening as well as 5-Volt's ending
cutscene.

9-Volt also appears in the Potluck Gang set of the Ultra League, where he goes on a camping trip with Orbulon, 18-Volt, Ashley and Red, Dribble and Spitz, Mike and 5-Volt.
 He asks the group what food they brought, saying that a potluck might
have been a bad idea after Ashley brings a mandrake root. He is then
seen playing cards with the rest of the group.