Mad Gear

The Mad Gear Gang features canonically in the first two Final Fight games as the main antagonists, plaguing the citizens of Metro City.

Story
The Mad Gear, led by Horace Belger, controlled virtually all of Metro City, from the slums to the transportation systems all the way to the uptown district and at least one policeman in their pocket. This situation came to a head when Mike Haggar was elected mayor after a campaign promising to be tough on crime.

Final FIght
The gang attempted to control the new mayor by kidnapping his daughter Jessica and holding her hostage. Rather than capitulating or negotiating, however, Haggar called on Jessica's boyfriend Cody and his best friend friend Guy and fought back. The trio assaulted every ringleader in the gang that they could lay their hands on until they located Jessica in Belger's penthouse apartment. In the ensuing fight Cody defenestrated Belger, leaving the gang reeling and leaderless.

Final Fight 2
The gang members that remained regrouped under the leadership of Belger. Guy, however, was away training with Zeku and was unaware of the situation, so Rena's sister Maki enlisted Haggar's help as well as that of a swordsman named Carlos Miyamoto. The new trio smashed Mad Gear hideouts around the world until learning from a defeated Rolento that Rena and Genryusai were being held in the gang's main headquarters in Japan. There, they fought and defeated Retu, and the Mad Gear have not recovered nor been heard from since.

Street Fighter series
Several members of the gang are known to have struck out on their own since the destruction of the gang, choosing paths as disparate as professional wrestling, to attempting to found a utopian nation, to continuing in law enforcement. What became of the rest of the gang, or even how many survived their wars against Haggar and his allies, is unknown.

Minions

 * Andore Family
 * Poison
 * Roxy - a palette swap of Poison with orange hair.
 * El Gado
 * Holly Wood - El Gado's palette swap. He sported a goatee, wore an orange hoodie with camo pants and a bandana on his head. In some occasions, he came dressed in red and brandishing molotov cocktails, which he threw at the heroes just before leaving. This version was much weaker than usual, and required only one hit to be killed off.
 * Axl - a muscle-bound thug who was able to defend oncoming attacks, unlike other opponents. He had shoulder-long blond hair and wore a headband.
 * Slash - Axl's palette swap. He had short, curly, dark hair in the SNES version, while the arcade has him wearing a pompadeur hairstyle like Elvis.
 * Two P and J - a pair of punks dressed in baggy pants and jackets. Two P sported an orange mohawk, wore shades, dressed in orange and blue and had a dragon symbol on his back, while J had his blond hair upright, dressed in yellow and dark blue and had an atomic biohazard symbol on his back. In the game, they tend to strike when the player has their back turned on one of them.
 * Bred - exemplified the look of a typical Mad Gear thug. It was his car that got trashed in the bonus round of Final Fight. He wore a light brown suit and had dirty blond hair.
 * Dug - Head swap of Bred dressed in red. He's bald and wears shades.
 * Jake - A bearded thug who dresses similar to Bred and Dug, only his outfit is blue and he wears a vest.
 * Simons - A gold-dressed head-swap of Jake with a clean shave face, short curly hair and shades.
 * Bill Bull, Graham Oriber and Wong Who - A group of bald, obese men wearing pants with suspenders. Their attacks consisted of a charging headbutt, a standing headbutt and a kick. Bill Bull sported a thick beard, G. Oriber sported a chinstrap, and Wong Who had a braided topknot with no facial hair.

Ringleaders

 * Damnd
 * Sodom
 * Edi E.
 * Rolento
 * Abigail
 * Belger

Minions

 * Atlas and Jony - A pair of scarred musclemen with strong defense.
 * Mic and Mark - are short and odd-looking thugs. They are fast, with punch attacks similar to Two P..
 * Bull and Elijah - take over the job of Bred as being the most basic enemies. Having a kick attack, they are also very predictable and are very slow.
 * Jack and Schot - are another form of basic thugs.
 * Elick - A pudgy man who wields an electrified tuning fork.
 * Elias and Eliot - A pair of club-wielding bad guys.
 * Mary and Eliza - A pair of athletic female knife wielders. Replaced by Leon and Robert in the international version.
 * Andore returns, along with Andore Jr. and G. Andore.

Ringleaders

 * Won Won
 * Freddie
 * Bratken
 * Philippe
 * Rolento - having been replaced in the home version of the original game, he was featured as a boss in the console-only Final Fight 2.
 * Retu

Trivia

 * The Mad Gear Gang was named after an earlier unrelated Capcom game named Mad Gear (LED Storm in the U.S.).
 * The Mad Gear Gang have cameos in the background of the destroyed Metro City stage in Marvel vs. Capcom 3: Fate of Two Worlds.
 * The Mad Gear Gang also have cameos in the background of a stage in Street Fighter X Tekken; Damnd, Axl, Edi E., Retu, Belger, a gray haired Andore, possibly Hugo's father and later, Sodom are seen dancing to Kabuki motions and playing to Japanese musical instruments.
 * Several of the members of Mad Gear are named after rock music elements (such as musicians, vocalists, band names and even album names), such as Poison named after a glam rock band of the same name, Roxy named after Roxy Music, Axl and Slash named after Guns 'n' Roses members Axl Rose and Slash, G. Oriber inspired by guitarist Graham Oliver, Abigail named after King Diamond's album of the same name (considering the character uses face paint like King Diamond), Simons based on Kiss' leader Gene Simmons.
 * According to his bio in Capcom Classics Collection, J is autistic and has an obsession with salads.
 * In 1993, the Mad Gear Gang appeared on the cover of SEGA's Mega Drive Fan magazine in Japan.