Renato Ruíz Cortes (born May 9, 1977), better known by his ring name Averno (Hell), is a Mexican professional wrestler, signed to Consejo Mundial de Lucha Libre (CMLL). Ruíz initially worked for (CMLL) as Rencor Latino in 1995, but did not achieve any significant success until he adopted the ring name Averno in June 2001. Under his new ring name, Ruíz went on to become a one–time CMLL World Middleweight, CMLL World Trios Champion, NWA World Middleweight Champion and NWA World Historic Middleweight Champion and a three–time CMLL World Tag Team Champion, and CMLL World Light Heavyweight Champion. His ring name is most commonly translated as "Hell" in English.

For many years Averno's real name was not a matter of public record, as is often the case with masked wrestlers in Mexico where their private lives are kept a secret from the wrestling fans. However, in May 2011, Averno was booked in a Lucha de Apuesta, where he lost his mask and was forced to reveal his true identity. Ruíz left CMLL in April 2014 and joined rival promotion Lucha Libre AAA Worldwide (AAA) the following month.

Renato Ruíz Cortes was born on May 9, 1977, in Mexico City, Mexico, son of then-professional wrestler Rodolfo Ruíz. He began training for a professional wrestling career himself at a young age, training under his father, who by then had retired from in-ring competition and instead was working as a referee and trainer. He made his in-ring debut in 1995, around his eighteenth birthday.

Ruíz began wrestling in 1995 under the ring name Rencor Latino (Latin Hostility). Working as Rencor Latino he soon started working in the lower ranks of Consejo Mundial de Lucha Libre (CMLL; "World Wrestling Council"). He won his first Lucha de Apuestas, or "bet match", 1998 unmasking Apolo Chino by defeating him after a midcard feud. On August 4, 2002, Rencor Latino was one of twelve wrestlers putting their mask on the line during CMLL's Entre Torre Infernal ("In the Infernal Tower") pay-per-view. The match came down to Rencor Latino and veteran wrestler El Hijo del Gladiador, and ended with Rencor Latino winning the match, taking El Hijo del Gladiador's mask in the process. He continued wrestling in the midcard until he was recruited by El Satánico in the summer of 2001 to be part of a new Los Infernales ("The Infernal Ones") group.

During a televised segment Satánico used his supposed "satanic powers" to turn técnico (good guy) Rencor Latino into one of his "minions", a rudo (bad guy) character known as "Averno" ("Hell"). Traditionally when a masked wrestler transitions from one identity to a new identity it is not publicly acknowledged, but in Ruíz' case it was actually part of the storyline. As a result of the transition Averno would on occasion wrestle wearing a special mask that was half Averno, half Rencor Latino. Satánico and Averno were joined by Mephisto who had previously wrestled as Astro Rey Jr. The trio feuded with Último Guerrero, Rey Bucanero, and Tarzan Boy throughout the year with Averno and El Satánico unsuccessfully challenging Guerrero and Bucanero for the CMLL World Tag Team Championship in August 2001. The team lost when Satánico was disqualified for using a low blow. When Tarzan Boy was injured and unable to wrestle Bucanero and Guerrero recruited Máscara Mágica to even the numbers. The storyline between the two factions reaches its high point at the CMLL 68th Anniversary Show where all seven wrestlers faced off in a steel cage match. The stipulation of the match was that the winning side would gain the rights to use the name Los Infernales while the loser on the opposite side would be forced to unmask or have their hair shaved off. In the end El Satánico pinned Máscara Mágica, forcing him to unmask. After losing the match Guerrero, Bucanero and Tarzan Boy became known collectively as Los Guerreros del Infierno (The Infernal Soldiers), while El Satánico, Averno and Mephisto continuing to work as Los Infernales.

In 2002, Los Infernales won the Mexican National Trios Championship in Guadalajara, Jalisco and began feuding with La Familia de Tijuana (Nicho el Millonario, Halloween, and Damián 666). The trio lost the championship to La Familia in September 2002 but continued feuding with the group into 2003. Over the summer of 2003 Los Infernales won a tournament to become the number one contenders for the CMLL World Trios Championship but lost champions Black Tiger III, Dr. Wagner Jr., and Universo 2000 on August 1. At the end of the year, Averno and Mephisto turned on El Satánico, but there was no major storyline feud between the three afterwards. In September 2004, Averno defeated Zumbido to win the vacant NWA World Middleweight Championship. Shortly after the championship win Averno was positioned as a rival or foil to the up-and-coming tecnico Místico. Averno and Mephisto also became de facto members of Los Guerreros del Infierno, joining forces with their former rivals. In February 2005, Averno lost the NWA World Middleweight Championship to Místico as part of their long running storyline. Two months later Averno and Mephisto defeated Atlantis and Blue Panther to win the CMLL World Tag Team Championship. When Shinsuke Nakamura and Hiroshi Tanahashi from New Japan Pro-Wrestling came to CMLL, Averno initially teamed up with them, the two turned on him. This led to a trios match with Averno, Último Guerrero and Rey Bucanero defeating Nakamura, Tanahashi, and Shigeo Okumura in one of the featured bouts on the CMLL 72nd Anniversary Show. In early 2006 Averno and Mephisto were the catalyst for one of CMLL's big storylines as they defended their titles against Místico and Black Warrior twice. In the first match, they won by disqualification when Black Warrior interfered in the match after already being eliminated and in the second match Black Warrior turned on Místico, attacking his partner to end the match. In April 2006, they lost the tag team championship to Místico and Negro Casas, ending their 377-day-long reign.

In 2008 Averno formed the group Los Hijos del Averno ("The Sons of Hell") alongside Mephisto and Ephesto, followed by Averno and Mephisto defeating Atlantis and Último Guerrero to win the CMLL World Tag Team Championship for a second time. On September 17, 2008, Averno defeated Negro Casas to win the CMLL World Middleweight Championship, becoming a double middleweight champion as he still held the NWA World Middleweight Championship. Their reign lasted only 38 days before Místico and Héctor Garza won the championship from them. The duo became three-time tag team champions by the end of the year as Averno and Mephisto defeated Místico and Garza on December 7, 2008. The duo's third run with the CMLL World Tag Teams Championship ended on January 16, 2009, when they lost to La Sombra and Volador Jr. On July 22, Averno lost one of his middleweight championships, the CMLL World Middleweight Championship, to Hijo del Fantasma. On July 12, 2010, at the Promociones Gutiérrez 1st Anniversary Show Averno participated in a match where 10 men put their mask on the line in a match that featured five pareja incredibles teams, with the losing team being forced to wrestle each other with their mask on the line. His partner in the match was Último Guerrero, facing off against the teams of Atlantis and Olímpico, Místico and El Oriental, Histeria and La Sombra, Volado Jr. and El Alebrije. Averno and Último Guerrero was the third team to escape the match. In mid 2010 CMLL abandoned the NWA World Middleweight Championship after repeated complaints from the National Wrestling Alliance, instead they created the NWA World Historic Middleweight Championship and made Averno the first champion. Averno was one of 14 men putting their masks on the line in a Lucha de Apuestas steel cage match, the main event of the CMLL 77th Anniversary Show. Averno was the first man to leave the steel cage with all three members of Los Hijos del Averno quickly leaving the cage, keeping their masks safe.

In April 2011, Averno began feuding with La Máscara, building a storyline that led to a Mask vs. Mask Lucha de Apuesta on June 17. The match announcement came on the heels of a report that Averno had signed a contract with WWE, supposedly following long time in-ring rival Místico who had already signed with WWE. On June 17 at CMLL's Juicio Final ("Final Judgement") show, Averno was defeated by La Máscara two falls to one and thus was forced to unmask. Upon unmasking, Averno revealed that his real name was Renato Ruíz Cortes, that he was 34 years old originally from Mexico City and had been wrestling for 16 years. Afterward, Ruíz and La Máscara continued their rivalry, building up to another singles match on July 4, where Ruíz successfully defended the NWA World Historic Middleweight Championship. Despite rumors Averno never began working for WWE, opting at the time to stay with CMLL. On July 15, Los Hijos del Averno defeated La Generación Dorada (La Máscara, Máscara Dorada and La Sombra) to win the CMLL World Trios Championship. On September 9, 2011, Averno entered CMLL's annual tournament of champions, the Universal Championship tournament. After defeating CMLL World Super Lightweight Champion Virus and old rival, Mexican National Light Heavyweight Champion La Máscara, in his first two matches, Averno defeated CMLL World Tag Team Champion Último Guerrero in the semi-finals. On September 16, Averno was defeated in the Universal Championship finals by La Sombra. On November 22, Averno lost the NWA World Historic Middleweight Championship to La Máscara.