On the August 12 episode of SmackDown, Sin Cara (as Hunico) made his WWE television debut, when he took over the role of the original Sin Cara from the real Sin Cara, who was serving a 30 day suspension for violating WWE's wellness program, and defeated Tyson Kidd in a singles match. Hunico reprised his role of Sin Cara the following week, taking part in a battle royal to determine the number one contender to the World Heavyweight Championship, from which he was the last man eliminated by the winner, Mark Henry. On August 20, the original Sin Cara took back the role of Sin Cara for a live event, however, at the following tapings of SmackDown, Hunico once again appeared under the mask. On the August 30 episode of SmackDown, Sin Cara defeated Daniel Bryan. After the match and as Bryan was recovering, Sin Cara went to shake his hand, then proceeded to roundhouse kick him in the head, turning heel in the process. At the tapings of the September 16 episode of SmackDown, the original Sin Cara made his return, confronting Hunico's impostor version of the character. On the September 19 episode of Raw, the impostor Sin Cara attacked the original character prior to his match with Cody Rhodes, but was forced to flee the ring after a brief brawl. On the September 23 episode of SmackDown, the impostor Sin Cara attacked the original version during his match with Daniel Bryan, then took his place in the match and pinned Bryan for the win. The following week he revealed a new black attire to distinguish himself from the original version, while also explaining that he was going to steal the Sin Cara identity from the original. On October 2 at Hell in a Cell, the impostor Sin Cara, now being referred to as "Sin Cara Negro", was defeated by the original Sin Cara, now referred to as "Sin Cara Azul". However, the feud continued on the following episode of SmackDown with Sin Cara Negro attacking Sin Cara Azul. The rivalry culminated at the October 16 taping of SmackDown in Mexico City in a Mask vs. Mask match, where Sin Cara Azul was victorious, unmasking Hunico by force after the match.
On the October 28 episode of SmackDown, Negro was interviewed by Matt Striker, where he wanted payback for losing to Azul while revealing his name to be Hunico. He also began to adopt a new gimmick, portraying a stereotypical Mexican hoodlum, wrestling in street attire and entering the arena on a lowrider bicycle. On the November 4 episode of SmackDown, Hunico continued his rivalry with Sin Cara by attacking him together with his debuting tag team partner Epico. However, this association was short lived as Epico went on to form a stable with Primo and Rosa Mendes. Hunico's feud with Sin Cara was cut short when Sin Cara suffered a legit injury at the 2011 Survivor Series which required surgery. On the December 15 episode of Superstars, Hunico came to the ring with Camacho (son of Haku) as his new bodyguard, before defeating Trent Barreta. On the December 30 episode of SmackDown, Hunico was accompanied by Camacho to a match with Justin Gabriel where Hunico was successful. After the match, Camacho would assist Hunico in attacking Gabriel. Hunico then started a feud with Ted DiBiase after Hunico was offended that he was not invited to one of DiBiase's Posse parties. Although DiBiase beat Hunico in a flag match, Hunico emerged victorious in two regular singles matches against DiBiase. At the Royal Rumble, he enetered at number 16, but was eventually eliminated by the returning Kharma. Hunico defeated DiBiase on the February 17 episode of SmackDown to end the feud. In June, Hunico would lose to Sin Cara, who returned from injury, on the June 4 episode of Raw and at the No Way Out pay-per-view. In the pre-show of Money in the Bank, Hunico and Camcho lost to the WWE Tag Team Champions Kofi Kingston and R-Truth in a non-title match.
At Raw 1,000, Hunico, along with Camacho and four other wrestlers attempted to ambush Kane to make a statement, but The Undertaker returned to save Kane, disposing of Hunico with a chokeslam and a tombstone piledriver. Hunico then underwent surgery for a torn ACL. He returned in December at a live event.
Hunico also returned at the Wrestlemania Axxess live event on April 4, 2013, once again teaming with Camacho. On the November 6 edition of Main Event, they returned to action on TV in a loss to The Usos. Hunico would make his return alongside Camacho to WWE Smackdown on the November 15th, edition losing in a handicap match to The Great Khali.
During the December 2nd edition of RAW, Hunico reprised his role role of Sin Cara in a clean win against Alberto Del Rio, and the character experienced a resurgence as he went on a winning streak that continued through December. Sin Cara's streak was ended by Del Rio on the January 6, 2014 episode of Raw. Sin Cara would go on to compete in the Andre the Giant Memorial Battle Royal at WrestleMania XXX, only to be eliminated by Alberto Del Rio. On the May 23 episode of SmackDown, Sin Cara would lose to the debuting Bo Dallas. Sin Cara would go on to lose a Money in the Bank qualifying battle royal in June and a battle royal for the WWE Intercontinental Championship at Battleground. Around this time, Sin Cara was sent to NXT, where he made a tag team with Kalisto known as Lucha Dragons. At NXT Takeover: Fatal Four-Way, Sin Cara and Kalisto defeated The Ascension to win the NXT Tag Team Championship, and Sin Cara's first title in WWE.
After defeating Intercontinental Champion Bad News Barrett in a non-title match on the January 9, 2015 episode of SmackDown, Sin Cara was awarded a title shot against Barrett on the taped episode of Smackdown which aired on January 15, but lost the match. At the NXT tapings on January 15, the Lucha Dragons lost the NXT Tag Team Championship to Buddy Murphy and Wesley Blake. Cara would also enter the Royal Rumble match, but would be quickly eliminated. Sin Cara participated in the 2nd Annual André the Giant Memorial Battle Royal at WrestleMania 31 but failed to win the match. The following night on Raw, the Lucha Dragons made their main roster debut as a tag-team in an 8-man tag-team match, teaming with The New Day to defeat Tyson Kidd and Cesaro and the Ascension. At Elimination Chamber in May, the Lucha Dragons competed in the first ever tag team Elimination Chamber match for the WWE Tag Team Championship, however they failed to capture the titles. In late June, The Lucha Dragons took a small part in the ongoing feud between the New Day and the Prime Time Players on the 25 June episode of Smackdown, when they teamed with PTP in a winning effort against the New Day and Bo Dallas. The Lucha Dragons and PTP teamed up again on the next episode of Raw, and defeated Dallas and New Day for a second time. At SummerSlam (2015), The Lucha Dragons competed in a Fatal 4-Way tag team match for the WWE Tag Team Championship which was won by The New Day. At Night of Champions (2015), The Lucha Dragons and Neville were defeated by The Cosmic Wasteland (Stardust and The Ascension (Konnor and Viktor)). At TLC: Tables, Ladders and Chairs (2015), The Lucha Dragons, The Usos and The New Day competed in a triple threat tag team ladder match for WWE Tag Team Championship which was won by The New Day.
On the December 28, 2015 edition of Raw, Cara dislocated his shoulder in a match with Big E. On February 6, 2016, at a live event, Sin Cara returned from injury, teaming with Kalisto in a winning effort against Los Matadores. Cara made his television return on February 8, teaming with Kalisto in a losing effort against Alberto Del Rio and Rusev. On the March 21 episode of Raw, Sin Cara faced Stardust and Zack Ryder in a triple threat match to determine the number one contender for the WWE Intercontinental Championship, which ended in no contest, after Intercontinental Champion Kevin Owens interfered in the match. Afterwards, it was announced that Sin Cara would compete in a 7-man ladder match for the title at WrestleMania 32 against Owens, Stardust, Ryder, Sami Zayn, The Miz and Dolph Ziggler, in which Cara was unsuccessful. On the May 9 episode of Raw, Sin Cara faced his partner Kalisto's Extreme Rules rival Rusev with Kalisto outside the ring. Rusev had the advantage until a distraction from the official allowed Kalisto to interfere and kick Rusev in the head, gaining an advantage for Sin Cara who pinned Rusev for the win. On July 18, Sin Cara and Kalisto announced they were done as a tag team and were entering the 2016 WWE draft as singles competitors. As a result of the draft, Sin Cara was drafted to the Raw brand, while Kalisto was drafted to SmackDown.
On the September 5 episode of Raw, Sin Cara confronted Braun Strowman, who had removed a luchador's mask the previous week. Sin Cara berated Strowman for disrespecting luchador tradition, igniting a feud between the two. They went on to have two matches, where Strowman would win via countout and pinfall, respectively. On the October 10 edition of Raw, Cara competed in a cruiserweight match, teaming with Lince Dorado, beating the team of Tony Nese and Drew Gulak. During the match it was confirmed that Cara will now be competing in the cruiserweight division full time.