In June 2016, Del Toro was announced as a participant in the WWE Cruiserweight Classic, a 32-man single-elimination tournament featuring competitors 205 lbs. and under, as a representative from Mexico under the name Raul Mendoza. Mendoza was eliminated from the tournament in the first round by The Brian Kendrick. Following the Cruiserweight Classic, Mendoza was signed by WWE, who assigned him to compete in the NXT developmental territory. Mendoza made his NXT debut on the May 25, 2017 episode, being defeated by Velveteen Dream. On February 9, 2018 at an NXT live event, Mendoza won a battle royal to become the number one contender to the NXT Championship. The following day on February 10, Mendoza was defeated by NXT Champion Andrade "Cien" Almas. Mendoza made his debut on the July 23, 2019 episode of 205 Live, where he teamed with Humberto Carrillo to defeat Kalisto and Gran Metalik. On the November 1 episode of 205 Live, Mendoza unsuccessfully challenged the NXT Cruiserweight Champion Lio Rush.
On the March 11, 2020 episode of NXT, Mendoza was abducted by a group of masked men and thrown into a van in the parking lot in what was originally an interview of Mia Yim. On the April 1 episode of NXT, Joaquin Wilde was similarly abducted during a post-match interview. On the June 10 episode of NXT, Mendoza made his return as he along with Wilde were revealed as the mysterious masked men and they aligned themselves with Santos Escobar as they attacked Drake Maverick, thus turning Mendoza heel. On night one of The Great American Bash, the trio was named Legado del Fantasma. In their first match as a team, Legado del Fantasma defeated Maverick and Breezango in a six-man tag team match on the second night of The Great American Bash.
Wilde and Mendoza would then start competing in NXT's tag team division and 205 Live. At NXT TakeOver: XXX, Wilde and Mendoza competed against Breezango (Fandango and Tyler Breeze) and the team of Oney Lorcan and Danny Burch in a triple threat match to determine the number one contenders for the NXT Tag Team Championship, but were unsuccessful in winning the match. On night one of NXT Super Tuesday, Legado lost to Isaiah "Swerve" Scott and Breezango in a street fight when Scott pinned Escobar, leading up to a match between Escobar and Scott for Escobar's Cruiserweight Championship at NXT TakeOver: 31, where Wilde and Mendoza assisted Escobar in retaining the title.
In 2021, Wilde and Mendoza entered the 2021 Dusty Rhodes Tag Team Classic, in which they lost to the eventual winners MSK (Nash Carter and Wes Lee) in the semifinal round. They also faced MSK and Grizzled Young Veterans (James Drake and Zack Gibson) on night one of NXT TakeOver: Stand and Deliver in a match with the Tag Team Titles on the line, which MSK won. At NXT TakeOver: In Your House, Legado del Fantasma would face NXT North American Champion Bronson Reed and NXT Tag Team Champions MSK in a winners take all, six man tag team match, in which Legado del Fantasma were unsuccessful in winning the titles. On the August 24 episode of NXT, Elektra Lopez made her debut helping Legado Del Fantasma win against Hit Row. In April 2020, Mendoza’s name would be changed to Cruz Del Toro.
On October 7, 2022 edition of SmackDown, Del Toro, alongside Wilde and Escobar, would join Zelina Vega on the SmackDown brand. On the March 10 episode of SmackDown, Wilde alongside the rest of Legado del Fantasma helped Rey Mysterio against The Judgment Day, turning face in the process. On the March 31 episode of SmackDown, Rey reformed the Latino World Order and invited Legado del Fantasma to join as a token of appreciation for aiding him in his fight against his son, Dominik, and The Judgment Day. On the November 10 episode of SmackDown, Escobar defected from LWO and removed Zelina Vega, Wilde and Del Toro from Legado del Fantasma the following week. Wilde and Del Toro participated in the 2024 Dusty Rhodes Tag Team Classic tournament, defeating Chase University's Duke Hudson and Riley Osborne on the January 16, 2024 episode of NXT, but lost to Carmelo Hayes and Trick Williams in the semifinals two weeks later. On night two of the 2024 WWE Draft, the LWO were drafted to the Raw brand.