Wario

"I'm-a Wario, I'm-a gonna win!"

- ~ Wario

"Wario time!"

Wario is Mario's arch-rival yet friend. He first appeared in Super Mario Land 2: Six Golden Coins for the Game Boy in 1992. He is rude, crude, selfish, and a bully - certainly not qualities associated with traditional heroes and indeed Wario is a borderline villain for the most part however Wario has been altered from a threat to a comedic nuisance who has actually become a hero of sorts in his own franchise (albeit a very greedy and flawed one).

Wario has even saved the world on numerous occasions, though it is normally done out of his love for gold and fame than for any true care about the world's safety (Wario is not completely heartless though, just a bit of an egomaniac). Wario had his own sidekick, Waluigi who is also bad and sometimes good.

In his early appearances, Wario wore a long-sleeved shirt and had magenta overalls, but in his later appearances, Wario wore a short-sleeved shirt and wore purple overalls.

Despite being a villain in Super Mario Land 2: Six Golden Coins, Wario's Woods and Wario Blast: Featuring Bomberman, Wario was an ally to Mario in later Mario games. Wario is not evil but a comic relief with anti-heroic purposes. Wario was an unlockable character seven times in Mario Golf for the Nintendo 64, the Game Boy Color version of Mario Golf and the Game Boy Color version of Mario Tennis, Yakuman DS, Mario Golf Advance Tour, Mario Kart 7 and Super Smash Bros. 4. He was playable in every Mario Party game except for Mario Party Advance. He was absent in the Game Boy Advance version of Mario Power Tennis.

Wario appeared in every Mario Kart game as a playable character except for Super Mario Kart. From Mario Kart 64 to Mario Kart DS, and Mario Kart 7, Wario's kart is purple, but in Mario Kart Wii and Mario Kart 8 his kart was yellow instead of purple, due to the color of his hat and shirt.

Personality
Wario is a greedy, selfish and rude bounty hunter. He's willing to scam his friends to get a lot of money or to take any job that pays well, despite the job itself. He's also hot headed and ill-tempered, especially against rivals like Mario.

However, Wario is not an evil man, but more of an anti-hero. He does possess heroic qualites, but often if he has something to gain on it.

Wario Land
Wario was a hero in this series, and teamed up with various allies to defeat various enemies and collect various treasures. Often his only goal was to collect treasures or get back home, with saving people just being a thing on the side to him.

Wario Ware
Wario is the CEO of WarioWare, Inc., and makes video games. He apparently lives in Diamond City and has numerous friends. He often scams his friends into doing work for him to profit from, yet they don't seem to hold grudges.

Super Smash Bros.
Wario's clothes were one of Mario's alt. costumes in the game.

Same is in the next game, but Wario was made into a trophy. He originally was going to be in it, but was cut.

In Brawl, Wario finally makes it as a playable character, in his biker outfit, but has his classic outfit as an alternate costume. He was a member of the Subspace in Story Mode, but became good and helped Luigi, Ness and King Dedede defeat Tabuu.

In SSB4, Wario is in it again, but as an unlockable character. He is quicker than his Brawl version though.

Mario And Sonic
Wario is a playable character in Mario & Sonic at the Olympic Games, Mario & Sonic at the Olympic Winter Games, Mario & Sonic at the London 2012 Olympic Games, and Mario & Sonic at the Rio 2016 Olympic Games. In the first three games, he is a Power-type character.

Trivia

 * One of Wario's alternate costumes in the Super Smash Bros. series is based on Mario's outfit from the early Mario games and in the three DIC cartoon adaptations.
 * Wario is similar to Shadow the Hedgehog from Sonic the Hedgehog series: as both of them are anti-heroes and are the arch-rivals of Mario and Sonic. However, the difference between them is while Wario is rude, crude, funny and greedy, Shadow is very arrogant, serious and stubborn. Plus Shadow is a loner who would rather work alone.
 * Both of them were the main antagonists in their debut appearances.
 * Both are the second most popular characters of their franchises.
 * Both of them are very competitive and jealous of other people.
 * Both are neutral who do good and bad to achieve their goals.
 * Both of them are very ill-tempered and hot-headed.