Gonzalez was brought into AAA initially still with the Leon Negro gimmick. At Triplemanía V-A he won the hair of both Halcon Dorado, Jr. and May Flowers, teaming with Heavy Metal. Later that year he was chosen to replace the original Psicosis who was wrestling full-time in World Championship Wrestling (WCW) at the time, so Antonio Peña needed someone to take over the very popular character in AAA. He made his debut as Psicosis in mid-1998 siding with Los Vipers leader Cibernético and quickly became a core member of Los Vipers. On August 23, 1998, Psicosis, Histeria, Maniaco, and Mosco de la Merced teamed up to participate in a tournament for the vacant Mexican National Atómicos Championship, representing Los Vipers. Los Vipers won the tournament by defeating Los Payasos (Coco Amarillo, Coco Azul, Coco Negro, and Coco Rojo) in the finals to win the Atómicos title. Over the following months Los Vipers began a storyline feud with another group called Los Vatos Locos, which at the time consisted of Charly Manson, May Flowers, Nygma, and Picudo. On February 14, 1999, Los Vatos Locos defeated Los Vipers to win the Atómicos championship. Los Vipers won the title a second time on September 17, 1999, when they defeated Los Junior Atómicos (Blue Demon, Jr., La Parka, Jr., Mascara Sagrada, Jr. and Perro Aguayo, Jr.). Los Vatos Locos managed to end Los Vipers second reign only three months later as they defeated Psicosis and partners on the undercard of the 1999 Guerra de Titanes show. Los Vipers regained the Atómicos title on April 15, 2000. effectively ending the storyline with Los Vatos Locos. Los Vipers reigned as Atómicos champions for over a year, until they were surprisingly upset by a little-known group called Los Regio Guapos (Hator, Monje Negro, Jr., Potro, Jr.. and Tigre Universitario) on August 19, 2001. Los Regio Guapos only held the title for under two months before Los Vipers regained the title and began their fourth reign with the Atómicos title. Their fourth reign also turned out to be the last reign for Los Vipers, ending on November 23, 2001, as a new version of Los Vatos Locos (Espiritu, Nygma, Picudo and Silver Cat) defeated them in one of the featured matches of the 2001 Guerra de Titanes. Following the loss both Maniaco and Mosco de la Merced began appearing less and less for AAA. On August 13, 2002, Psicosis won his first singles championship as he defeated Pimpinela Escarlata to win the Mexican National Middleweight Championship. His reign as Middleweight champion was characterized by long periods where the title was not even defended, stretching his title reign out for almost three years. During this time period Psicosis turned técnico as he joined "The Mexican Powers" along with Juventud Guerrera, Crazy Boy, and Joe Lider. In early 2005 the original Psicosis returned to AAA and immediately began a storyline with Psicosis II over the rights to the name. The storyline included a steel cage match that took place at Triplemanía XIII, but ended in a no contest as Psicosis II's former partner Histeria interfered in the match when he attacked both wrestlers. Subsequently, the feud over the Psicosis name became a three-way feud between the Original Psicosis, Psicosis II, and Histeria. On August 3, 2005, Psicosis II successfully defended the Mexican Middleweight title against Histeria in a hardcore match. Following the match the Mexico City Boxing and Wrestling Commission, who regulate the Mexican National championships, stripped Psicosis II of the title since the rules state that Mexican National Championships can only be defended in regular matches, not Hardcore matches. The feud for the Psicosis name ended with Histeria winning a ladder match, earning the rights to the name. Histeria later handed the rights over to Antonio Peña, who decided to allow Psicosis II to keep the ring character, making the storyline a moot point. On October 18, 2006, The Mexican Powers defeated The Black Family (Cuervo, Chessman, Escoria, and Ozz) to win the Mexican National Atómicos Championship, Psicosis II's fifth reign. On May 20, 2007, Psicosis II turned on his partners during a title defense, allowing La Secta de Mesias (Cuervo, Escoria, Espiritu, and Ozz) to win the title. Psicosis II joined Histeria and Abismo Negro to reform Los Vipers, this time called Viper's Revolucion. Later on when Mr. Niebla joined the group both Psicosis and Histeria sided with him and kicked Abismo Negro out of the group. Viper's Revolucion was later joined by Black Abyss, an Abismo Negro clone. The feud with Abismo Negro was supposed to be settled at Triplemanía XVI in a cage match, but it was cancelled in the weeks leading up to the event, followed by Mr. Niebla leaving AAA. Following Mr. Niebla's defection from AAA Psicosis II, Histeria, and Black Abyss were used less frequently and not in any long term storylines.