The event took place on Saturday, September 30, 2023, and was live-streamed from the Mechanics Bank Arena in Bakersfield, California.

This was WWE's first livestreaming event in which the company was not owned and controlled by the McMahon family, as the company's sale to Endeavor was finalized on September 12, 2023, with WWE and Ultimate Fighting Championship merging to become divisions of a new entity called TKO Group Holdings.

In the main event, Raw's Becky Lynch defeated Tiffany Stratton in an Extreme Rules match to retain the NXT Women's Championship.

In another prominent match, Ilja Dragunov defeated Carmelo Hayes to win the NXT Championship.

No Mercy was first held by the American professional wrestling promotion WWE as a United Kingdom-exclusive pay-per-view (PPV) in May 1999.

[3] No Mercy was discontinued in 2009, but it was reinstated in October 2016 following the reintroduction of the brand extension, which brought back brand-exclusive PPVs.

[8] Hours before WrestleMania 39 Night 2 began, CNBC reported via multiple sources that a deal between WWE and Endeavor, the parent company of Ultimate Fighting Championship (UFC) via Zuffa, was imminent.

The deal involved a merger of WWE with the UFC into a new publicly traded company, with Endeavor holding a 51% stake.

[9] The sale was confirmed the next day on April 3, 2023,[10] and was finalized on September 12, with WWE merging with the UFC to become divisions of TKO Group Holdings.

The letter stated that on the next episode, a global number one contender's tournament would start, and Dar would defend the Heritage Cup against the winner at No Mercy.

[19] In the final on September 26, Butch defeated Coffey, earning an NXT Heritage Cup championship match against Dar at No Mercy.

[20] On the September 12 episode of NXT, Baron Corbin praised Bron Breakker for (kayfabe) crushing Von Wagner's skull with the steel steps the previous week.

[24] At The Great American Bash, Carmelo Hayes defeated Ilja Dragunov to retain the NXT Championship.

[27] On September 26, Shawn Michaels announced on X that a triple threat match would be held on that night's episode of NXT between Lee, Axiom, and Tyler Bate to determine who would instead challenge Mysterio for the title at No Mercy.

In the opening stages, Breakker delivered a somersault plancha and a release Northern lights suplex for a two-count.

As Corbin was attempting the End of Days, Breakker countered it into an inside cradle for a nearfall.

[28] Next, "Dirty" Dominik Mysterio defended the NXT North American Championship against Trick Williams with Dragon Lee serving as the special guest referee.

Williams then delivered a leg lariat, but as he was attempting a pop-up haymaker, Dominik countered it into a backslide pin for a two-count.

[28] The next match fatal four-way tag team match in which The Family (Tony D'Angelo and Channing "Stacks" Lorenzo) defended the NXT Tag Team Championship against The Creed Brothers (Brutus Creed and Julius Creed, accompanied by Ivy Nile), the team of Angel Garza and Humberto Carrillo, and OTM (Bronco Nima and Lucien Price, accompanied by Scrypts).

[28] In the fourth match, Noam Dar (accompanied by Jakara Jackson, Lash Legend, and Oro Mensah) defended the NXT Heritage Cup Championship against Butch (accompanied by Tyler Bate) in a British Rounds Rules match.

Dragunov then delivered a deadlift superplex, but as he was attempting the Torpedo Moscow, Hayes impeded it with a Codebreaker.

[28] In the main event, Becky Lynch defended the NXT Women's Championship against Tiffany Stratton in an Extreme Rules match.

As Becky was attempting the Dis-Arm-Her, Stratton blocked it and delivered a side walk slam for a two-count.

Stratton then delivered a cannonball senton to Lynch onto the announce table and a Swanton Bomb for a nearfall.

[29] On the following episode of Raw, Rhea Ripley announced that "Dirty" Dominik Mysterio had a rematch against Trick Williams for the NXT North American Championship on the next night's NXT with the added stipulation that if Mysterio did not regain the title, he would not be welcomed back into The Judgment Day.

[30] On NXT, Mysterio defeated Williams to regain the championship and retain his Judgment Day membership thanks to interference from his stablemates, Ripley, Finn Bálor, and Damian Priest, as well as their accomplice, JD McDonagh.