Frontier Martial-Arts Wrestling (1989–1998)
Following his return to the ring, Onita issued a challenge to the wrestlers of the shoot style promotion Universal Wrestling Federation (UWF) but his challenge was rejected and he responded by taking on martial artist Masashi Aoyagi in a (worked) martial arts fight for the World Karate Association (WKA) on July 2, 1989, during which Onita was disqualified for using wrestling moves on Aoyagi. In the aftermath of his fight for the WKA, Onita personally promoted two wrestling shows under the Frontier Martial-Arts Wrestling (FMW) banner titled Grudge in Nagoya and Grudge in Tokyo in October and headlined both shows against Aoyagi. He lost to Aoyagi at Grudge in Nagoya and defeated him at Grudge in Tokyo. Onita shortly after developed FMW into a full-time promotion, originally basing it around shoot style matches before transitioning the company into being Japan's first death match promotion – taking inspiration from the style of matches he had seen during his earlier stay in Memphis. Even as the deathmatch wrestling style become the main trademark of FMW, the promotion would continue to hold shoot style matches. Onita would bring in numerous karate and martial arts fighters to be part of the FMW roster in the early years of the promotion.
The first street fight of FMW took place on December 4, in which Onita and Dick Murdoch defeated Jos LeDuc and Masanobu Kurisu. Onita was featured as the company's main star and the top fan favorite and headlined every show. His first Barbed Wire Deathmatch took place at Battle Creation as he teamed with Tarzan Goto to defeat Jerry Blayman and Mitsuhiro Matsunaga. After being eliminated by his frequent ally Tarzan Goto from the Battle Resistance tournament, Onita defeated Beast the Barbarian to win the WWA World Brass Knuckles Heavyweight Championship for the first time on January 17, 1990.
Onita's first feud began in the summer of 1990 when Onita defeated Lee Gak-soo in a different style fight on May 19 and then the two showed respect to each other and teamed to defeat Mitsuteru Tokuda and Sambo Asako in a tag team match on June 2. Goto was irate at Onita for teaming with karate fighters and toning down professional wrestling and he brought in Mr. Pogo to FMW and Onita began feuding with Goto and Pogo. Onita defeated Goto in an empty arena match on June 24 and then successfully defended the Brass Knuckles Heavyweight Championship against Goto in the first-ever no ropes exploding barbed wire deathmatch at Summer Spectacular. After the match, Onita and Goto ended their feud by embracing each other and putting away their differences and then Onita began a legendary rivalry against Mr. Pogo, with Onita defeating Pogo in the first singles encounter in a street fight on August 25. Onita successfully defended the Brass Knuckles Heavyweight Championship against Pogo in a Texas Deathmatch at 1st Anniversary Show.
Onita lost the Brass Knuckles Heavyweight Championship to Grigory Verichev on February 27, 1991. Onita unsuccessfully challenged Verichev for the title in a rematch on May 5 and then received another title shot on May 29, where Onita defeated Verichev to regain the renamed World Martial Arts Heavyweight Championship. On August 17, Onita defeated Jimmy Backlund, Ricky Fuji and Sambo Asako to win the Barbed Wire Deathmatch Tournament. During this time, Mr. Pogo left FMW and Tarzan Goto turned on Onita once again to renew their feud and became Onita's arch rival. Onita defeated Goto in the first-ever no rope exploding barbed wire steel cage deathmatch at the very successful 2nd Anniversary Show on September 23 at the Kawasaki Stadium in Kawasaki, which would become the venue for FMW's major events in future.
Onita and Goto reunited once again and they participated in the World's Strongest Tag Team Tournament, which they won by defeating Grigory Verichev and Koba Krutanize in the final on December 9 to win the inaugural WWA World Martial Arts Tag Team Championship. FMW phased away the martial arts style and emphasized on the deathmatch wrestling as its key feature during this time. Onita lost his World Martial Arts Heavyweight Championship to Big Titan on January 15, 1992. Onita and Goto lost the World Martial Arts Tag Team Championship to Sabu and Horace Boulder in a no ropes barbed wire street fight deathmatch on May 7. Onita regained the World Martial Arts Heavyweight Championship by defeating former boxing champion Leon Spinks in a cage match on May 24, which earned a rapid rise in popularity and stardom to Onita for having beaten a famous celebrity. A month later, Onita lost the title to The Sheik on June 25 because of an injury sustained from an attack by Tiger Jeet Singh before the match. Sheik would later reward the title to Singh. Onita lost to Singh in a jungle deathmatch on June 30, before defeating him in a no ropes exploding barbed wire deathmatch to win his fourth World Martial Arts Heavyweight Championship at the 3rd Anniversary Show.
Onita continued his success by winning the Street Fight Tournament with former rival Grigory Verichev on December 7. He ended his feud with The Sheik by defeating him for the United States Championship on January 18, 1993; Onita later returned the belt to Sheik saying that Sheik deserved the title for holding it for over a decade. This earned him Sheik's respect and both men ended their feud and became allies. Onita's success streak continued as he defeated Terry Funk in the first-ever no ropes exploding barbed wire time bomb deathmatch at the 4th Anniversary Show on May 5. Onita renewed his rivalry with Mr. Pogo, who returned to FMW in the summer of 1993 and the World Martial Arts Heavyweight Championship was replaced with the FMW Brass Knuckles Heavyweight Championship. Onita defeated Pogo in a no ropes exploding barbed wire time bomb deathmatch to win the vacant Brass Knuckles Heavyweight Championship at the Summer Spectacular show on August 22. Onita successfully defended the title against W*ING's former ace Mitsuhiro Matsunaga in a no ropes exploding barbed wire deathmatch at Year End Spectacular, and then the two men became allies to feud with Mr. Pogo and his entourage.
On January 6, 1994, Onita lost the Brass Knuckles Heavyweight Championship to Mr. Pogo in a street fight. After losing the title, Onita began his next feud with Genichiro Tenryu after the team of Onita and Tarzan Goto defeated Tenryu and Ashura Hara at Wrestling and Romance's Revolution Rumble when Onita pinned Tenryu. Onita and Tenryu competed in a no ropes exploding barbed wire deathmatch at 5th Anniversary Show on May 5, which stipulated that if Onita lost, he must retire from professional wrestling. Tenryu defeated Onita to even the scores and then Onita debuted his "Mr. Liar" character by saying that he was not going to retire immediately and that the retirement stipulation would take place a year later. Onita began his retirement tour which would conclude at the following year's 6th Anniversary Show. Onita reunited with Tenryu as the two teamed with Crusher Bam Bam Bigelow at WAR's 2nd Anniversary Show and the trio won a Six-Man Tag Team Tournament.
On July 31, Onita teamed with Mitsuhiro Matsunaga to defeat Mr. Pogo and Hisakatsu Oya to win the Brass Knuckles Tag Team Championship. Around the same time, Onita renewed his feud with Masashi Aoyagi, who had returned to FMW and attacked Onita after a match. Their rivalry culminated in a no ropes electrified explosive barbed wire barricade double hell match at Summer Spectacular, which Onita won. Onita defeated Mr. Pogo to win his sixth Brass Knuckles Heavyweight Championship on September 7. After the match, former W*ING wrestler Yukihiro Kanemura made his FMW debut and attacked Onita to avenge the demise of W*ING. Mitsuhiro Matsunaga visited Kanemura at hospital as Kanemura was getting treated for some burns which he had suffered during a past match. Onita accused Matsunaga of turning on FMW and mistrusting his loyalty and this angered Matsunaga, who then joined Kanemura and Mr. Pogo to form W*ING Alliance and Onita feuded with the group for the rest of his retirement tour. As a result, Onita and Matsunaga broke up as a team and vacated the Brass Knuckles Tag Team Championship in October.
On December 1, Onita debuted his alter ego "The Great Nita", which was based and stylized on The Great Muta. The team of Nita and Tarzan Goto defeated Hisakatsu Oya and Mr. Pogo in a no ropes exploding barbed wire double hell deathmatch. Onita would return as Nita to defeat Pogo in a lumberjack match on December 20 and would continue to use this alternative character on several occasions. Onita lost the Brass Knuckles Heavyweight Championship to Mr. Pogo's alter ego "Pogo Daiyo" on January 21, 1995. On February 24, Onita and his pupil Mr. Gannosuke defeated Pogo and The Gladiator to win the Brass Knuckles Tag Team Championship. They lost the title to Pogo and W*ING Kanemura on March 7. Speculation arose over the person to succeed Onita as the promotion's ace. Mitsuhiro Matsunaga had been the original choice but citing that W*ING had failed with Matsunaga as the ace, Onita had to change the decision and give the spot to Tarzan Goto, who would be Onita's opponent in his retirement match at the 6th Anniversary Show. Goto left FMW and took away his pupils Mr. Gannosuke and Flying Kid Ichihara as he was upset for putting over Onita again after having done it so many times in the past.
On March 30, Great Nita lost to Pogo Daiyo in a lumberjack match. Mr. Pogo refused to be Onita's opponent at 6th Anniversary Show and then Takashi Ishikawa was finally selected as the ace until Hayabusa interrupted Onita at a press conference and volunteered to be his opponent at the event as Hayabusa had been convinced by Shoichi Arai, whom Onita had sold the company around this time. Hayabusa was ultimately selected to be Onita's opponent in his retirement match. Just one day shy of his retirement match, Onita defeated Pogo in a barbed wire double hell deathmatch to win his record-setting seventh and final Brass Knuckles Heavyweight Championship on May 4. The following night at the 6th Anniversary Show, Onita successfully defended the title against Hayabusa in a no ropes exploding barbed wire deathmatch. After the match, Onita vacated the title due to his retirement from wrestling to pursue an acting career. During this time, he starred in the movie Dan Gan (Japanese for "bullet"), which would later be adopted as the nickname for Onita's pupil, Masato Tanaka. Onita's acting career flopped and he ventured a return to wrestling.
After a sabbatical (getting his high school diploma, as he had dropped out of high school when he was 16), Onita made a surprise return to FMW on March 15, 1996, along with his former rivals W*ING Alliance to rescue FMW's team from an attack by the Puerto Rican Army. He convinced the FMW wrestlers to challenge Puerto Rican Army at the 7th Anniversary Show and announced that he would be present in the crowd at the event. He also sold off his jacket that he wore for his retirement match at the 6th Anniversary Show to assist FMW team get the money for their match against the Puerto Rican Army. Onita made his next appearance on October 28, where his former rival Mr. Pogo begged him to come out of retirement and team with him against the Funk Masters of Wrestling in Pogo's retirement match at Year End Spectacular. Onita initially rejected Pogo's request and then rescued Pogo from an assault by Funk Masters of Wrestling on November 26 and agreed to come out of his retirement to team with Pogo. At the Year End Spectacular event, the FMW team of Onita, Pogo, Masato Tanaka and Tetsuhiro Kuroda defeated Funk Masters of Wrestling's Terry Funk, Hisakatsu Oya and The Headhunters in a Texas Tornado Street Fight Deathmatch.
Onita had supposedly returned to the company for only one match until he began working part-time for the company on March 14, 1997, by teaming with Koji Nakagawa, Masato Tanaka and Tetsuhiro Kuroda to defeat The Headhunters, Hisakatsu Oya and The Gladiator in a street fight. During this time, Onita also quietly ended his feud with W*ING Alliance as the group joined him in his feud with the Funk Masters of Wrestling. At the 8th Anniversary Show, the team of Onita, Masato Tanaka and W*ING Kanemura defeated Terry Funk, Cactus Jack and The Gladiator in a Texas Tornado Street Fight Deathmatch.
Onita headlined the Fall Spectacular event on September 28, 1997, against W*ING Kanemura in a no rope barbed wire electrified dynamite land mine time bomb death match, which stipulated that if Onita lost, he must retire and if Kanemura lost then W*ING Alliance would be forced to disband. Onita defeated Kanemura, forcing W*ING to disband. Onita became upset at the W*ING Alliance members Kanemura, Hideki Hosaka and Hido, who were upset as no group would accept them and he became enraged at FMW leaders Hayabusa, Koji Nakagawa and Masato Tanaka on their leadership of the FMW team. On September 30, Onita held a press conference in which he publicly denounced himself as a FMW wrestler and formed a New World Order (nWo)-themed faction ZEN with W*ING members and FMW wrestler Tetsuhiro Kuroda. As a result, Onita turned heel for the first and only time in FMW history. On October 14, the team of Onita, Hido and Kuroda defeated Hayabusa, Koji Nakagawa and Masato Tanaka to win the World Street Fight 6-Man Tag Team Championship.
On October 19, Onita and Yukihiro Kanemura defeated Mr. Gannosuke and Hisakatsu Oya to win the Brass Knuckles Tag Team Championship. Funk Masters of Wrestling came to an end as its leader Terry Funk left FMW, while the remaining members Mr. Gannosuke, Hisakatsu Oya and The Gladiator joined ZEN, which had now become the main villainous group in FMW against the FMW team led by Hayabusa. Onita and Kanemura were stripped of the Brass Knuckles Tag Team Championship in November due to Onita's inactivity and ZEN also lost the World Street Fight 6-Man Tag Team Championship to Hayabusa, Hisakatsu Oya and Masato Tanaka during the Super Extreme Wrestling War tour. During this tour, Mr. Gannosuke and Yukihiro Kanemura, along with Hido, grew upset at Onita for booking himself in the main event match on December 19 against Masato Tanaka instead of booking Gannosuke and Kanemura's match. This exploded when the team of Hayabusa, Jinsei Shinzaki and Masato Tanaka defeated Atsushi Onita, Mr. Gannosuke and Yukihiro Kanemura in a WarGames match on December 22. After the match, Gannosuke and Kanemura attacked Onita and quit ZEN, along with Hido and Koji Nakagawa joined Onita as ZEN's newest member. As a result, Onita reverted to being face along with ZEN.
ZEN began feuding with the newly formed Team No Respect, which evolved from legitimate heat between Onita and Kodo Fuyuki, who was getting a lot of influence and booking power in the company. Onita wanted to return FMW to its old deathmatch style ideology while Shoichi Arai and Kodo Fuyuki were toning down the deathmatch content. On February 13, Onita, Koji Nakagawa and Tetsuhiro Kuroda defeated TNR's Mr. Gannosuke, Yukihiro Kanemura and Jado to win the World Street Fight 6-Man Tag Team Championship. Onita's rivalry with Fuyuki would lead to a match between the two at 9th Anniversary Show, which stipulated that Onita must disband ZEN if he lost. Onita lost the lumberjack match and was forced to disband ZEN but he said that he would break the group only if Kodo Fuyuki, Yukihiro Kanemura and Hido would beat Onita, Koji Nakagawa and Tetsuhiro Kuroda for the World Street Fight 6-Man Tag Team Championship at ZEN's promoted show on May 5. Onita's team would lose after Nakagawa suffered an injury. Nakagawa continued to fake injury and would ultimately be revealed as the man responsible for breaking ZEN after he turned on Onita during a Brass Knuckles Tag Team Championship match against The New Footloose on May 31.
After the breakup of ZEN, Onita took a hiatus as he was unhappy with his position in the company. He made an appearance for FMW's working partner Extreme Championship Wrestling (ECW) on June 26 by costing The Sandman and Tommy Dreamer, a match against Dudley Boyz to set up a no ropes exploding barbed wire deathmatch against Sandman in ECW but the match never took place as Onita returned to FMW on July 20 to rescue Shoichi Arai from an assault by Team No Respect. At Atsushi Onita Presents Liar, Liar on August 11, Onita released his former ZEN teammates Hideki Hosaka and Tetsuhiro Kuroda from Team No Respect's slavery and saved Shoichi Arai's job as FMW President by defeating TNR in a weapons deathmatch. On August 21, Onita formed a group called Team Zero with Kuroda, Hosaka, Yoshinori Sasaki and Mr. Pogo #2 and the group feuded with TNR throughout the fall of 1998. Onita's former rival Mr. Pogo returned to FMW and the two feuded with each other, with Onita defeating Pogo in a match on November 20 to end their rivalry in FMW once and for all. This would be Onita's last match and last appearance in FMW as he left the company after the match as Shoichi Arai refused to restore him as the promotion's ace due to Onita receiving backlash from FMW's roster due to his reputation as an egomaniac and selfish.
