Keiichi Yamada (山田恵一, Yamada Keiichi, born November 10, 1964), better known as Jushin Liger (獣神ライガー, Jūshin Raigā) and later Jushin Thunder Liger (獣神サンダー・ライガー, Jūshin Sandā Raigā),[note 1] is a Japanese retired professional wrestler and mixed martial artist, signed to New Japan Pro-Wrestling (NJPW) as a trainer.

[9] By his own account, he was almost starving while studying in Mexico, due to this NJPW officials who were visiting took pity on him and asked him to come back to Japan to train in their dojo.

Throughout 1987 and 1988, Yamada improved with each match, occasionally getting shots at the IWGP Junior Heavyweight Championship, most notably against Owen Hart on June 10, 1988, and against Shiro Koshinaka on December 9, 1988.

Within months of his second Canadian excursion, NJPW called him back, as they needed him for a gimmick based on an extremely popular anime superhero, Jushin Liger, created by manga artist Go Nagai.

Years later, he started adapting more power moves and started focusing more on grappling and telling a story in the ring; part of this change was due to the fact that Liger had to reduce the stress he was putting on his body after undergoing brain tumor surgery in August 1996, which explained why he lost his match to Último Dragón in the first round of the J-Crown tournament.

During this time, Liger formed a faction called "Dragon Bombers" along with Tatsumi Fujinami, Shiro Koshinaka, Takayuki Iizuka and Black Cat and feuded with the Blond Outlaws group.

Liger claimed his record-setting fifth IWGP Junior Heavyweight Championship in the process and successfully defended both titles against Pegasus Kid on February 10.

Liger continued his IWGP Junior Heavyweight Championship reign with a successful title defense against Mad Bull Rex on March 9.

At Fantastic Story in Tokyo Dome, Liger defeated Último Dragón to capture his record setting sixth Junior Heavyweight Championship.

Later that year, Liger participated in the 1995 Super J-Cup on December 13, in which he defeated Gran Naniwa in the quarterfinals, Último Dragón in the semifinals and Gedo in the finals to win the tournament.

Liger defeated Koji Kanemoto to capture his record setting seventh IWGP Junior Heavyweight Championship at Wrestling World on January 4, 1996.

Liger would revive the character sporadically, relying on bloody and evil tactics in a match, using mannerisms and imagery that differ from the person's normal ways.

On November 3, Liger teamed with Muta in the One Night Tournament by defeating El Samurai and Tatsumi Fujinami in the opening round but lost to Akira Nogami and Michiyoshi Ohara in the semifinals.

After failing to advance in the 1999 Best of the Super Juniors, Liger and Sasuke lost the tag team titles to Shinjiro Otani and Tatsuhito Takaiwa on July 13.

At Wrestling Dontaku, Liger and Samurai successfully defended their tag team championship against the Mexican challengers Dr. Wagner Jr. and Silver King.

From 2004 to 2007, Liger was the leader of the NJPW heel stable Control Terrorism Unit (CTU) along with Hirooki Goto, Minoru Tanaka, Black Tiger IV, Gedo, Jado, Prince Devitt and briefly James Gibson.

Liger and Tiger won the vacant IWGP Junior Heavyweight Tag Team Championship on June 16, 2012, at Dominion 6.16,[24] losing it to Forever Hooligans (Alex Koslov and Rocky Romero) on July 22.

[28] At New Japan's 47th Anniversary Event, Liger was awarded a Junior Heavyweight Championship match against Taiji Ishimori after scoring a non-title victory over him the previous evening, however he failed to win the title losing via submission.

[11] Following his retirement, Liger remains in NJPW, serving as a trainer in the promotion's dojo and as a Japanese-language commentator for events on New Japan Pro-Wrestling World.

[36] Liger left WCW in December 1992 after Starrcade, teaming with Erik Watts in a losing effort to "Dr. Death" Steve Williams and Sting in a Lethal Lottery match.

[7] Liger was met with controversy around late-November/early-December 1999 while wrestling a short tour in WCW as the IWGP Junior Heavyweight Champion when he lost the championship on an episode of Monday Nitro to Juventud Guerrera via a blow to the head from a tequila bottle.

[46] Liger made his debut for the U.S.-based Total Nonstop Action Wrestling (TNA) promotion on October 23, 2005, as part of their Bound for Glory pay-per-view, losing to Samoa Joe.

[49] In 2007 Liger made a short visit to Mexico, working for Consejo Mundial de Lucha Libre (CMLL), NJPW's Mexican associate.

[50] Liger returned to CMLL in September 2009 for a longer tour, teaming with Okumura, Naito and Yujiro as La Ola Amarilla ("The Yellow Wave" in Spanish).

On the August 6, 2010 Super Viernes show Liger won Block B by defeating Negro Casas, Héctor Garza and La Máscara to earn a spot in the finals.

[56] On August 16, 2010, it was announced that Liger was one of 14 men putting their mask on the line in a Luchas de Apuestas steel cage match, the main event of the CMLL 77th Anniversary Show.

[64] On September 30 at CMLL's 78th Anniversary Show, Liger defeated eleven other men in a torneo cibernetico to advance to the finals of the 2011 Leyenda de Plata.

[73] On May 22, 2010, Liger made his debut for American promotion Jersey All Pro Wrestling (JAPW), losing to Homicide in the main event of the evening.

[74] He would return to the promotion seven months later on December 10, when he defeated Azrieal, Bandido Jr., B-Boy, El Generico and Kenny Omega in a six-way elimination match to win the JAPW Light Heavyweight Championship.

[80] Liger finished his American tour by teaming with Mike Quackenbush to defeat Jigsaw and The Shard in the main event of the Chikara show.