On August 23, 2018, Humberto Carrillo started competing for the WWE and signed his official contract on October 18, 2018, along with other recruits.
[5] Prior to that, Carrillo had made an appearance on the September 19 edition of NXT against Jaxson Ryker in a losing effort.
[6] On the December 5 edition of NXT, Carrillo would make his televised return when he teamed with Raul Mendoza in a losing effort against Steve Cutler and Wesley Blake of The Forgotten Sons.
[8] On the January 15, 2019 edition of 205 Live, Carrillo made his main roster debut when he answered the WWE Cruiserweight Champion Buddy Murphy's open challenge in a losing effort.
Despite this, General Manager Drake Maverick revealed after the show that Carrillo has joined the 205 Live roster and would compete at the WWE Worlds Collide Tournament at the Royal Rumble Axxess.
On August 27, 2019, Carrillo defeated Oney Lorcan to earn a title shot against Drew Gulak for the WWE Cruiserweight Championship at Clash of Champions.
[12] On the December 16 episode of Raw, Carrillo competed in a #1 Contender's Gauntlet match for the United States Championship but was defeated by Andrade after he was unable to continue following a DDT on the concrete floor which would sideline him for several weeks.
[14] Following this, Carrillo would begin a feud with his real-life cousin Angel Garza who Vega introduced as her newest protege and proceeded to attack him on the February 3, 2020 episode of Raw.
Carrillo returned to television on the April 9, 2021 episode of SmackDown participating in the André the Giant Memorial Battle Royal which he failed to win.
[17] On the September 20 episode of Raw, Carrillo formed a tag team with his cousin Angel Garza, thus turning heel for the first time in his career.
[18] The following week on Raw, Carrillo helped Garza defeat Erik using underhanded tactics, cementing his heel turn.
Later in the show, they were interviewed and said that they wanted to join the competition in the NXT tag division as Malik Blade and Edris Enofe, Josh Briggs and Brooks Jensen, and Hank Walker and Tank Ledger brawled in the ring.
[25] The following week, Carrillo and Garza made their in-ring return to the brand where they were defeated by Dragon Lee and Nathan Frazer.
[1] On the November 15 episode of SmackDown, United States Champion LA Knight announced an open challenge for the title, which was accepted by Legado Del Fantasma.