On the September 14, 2021 episode of NXT, Wagner made his debut, where he replaced Kyle O'Reilly, who was previously attacked by Pete Dunne and Ridge Holland in a fatal four-way match for the vacant NXT Championship against LA Knight, Pete Dunne and Tommaso Ciampa, in which he lost. On the November 30 episode of NXT, Wagner teamed with Kyle O'Reilly, winning a number one contender match after defeating Legado del Fantasma (Raul Mendoza and Joaquin Wilde). At WarGames, Wagner and O'Reilly challenged Imperium (Marcel Barthel and Fabian Aichner) for the NXT Tag Team Championship, but did not succeed in winning the titles. Enraged, Wagner attempted to attack O'Reilly from behind, but failed and was himself attacked instead. This led to a steel cage match between the two on the December 7 episode of NXT, which Wagner won.
Wagner later gained Mr. Stone as a manager. After opening up about his childhood struggles to Mr. Stone and a feud with Bron Breakker in August 2023, Wagner and Stone both turned face, shortly after Breakker himself turned heel. On the September 5 episode of NXT, Breakker injured Wagner with an attack on the steel steps.
On April 22, 2024, Wagner was released from WWE.