Wrestle Kingdom 9
On August 10, 2014, NJPW made two announcements. Firstly, Wrestle Kingdom 9 would be held at the Tokyo Dome on January 4, 2015. Secondly, NJPW revealed a partnership with Jeff Jarrett's Global Force Wrestling, which it approached about bringing the event to a new market. On November 4, GFW announced that it would present the event live on American pay-per-view television and that it had a PPV market of 125 million homes.
Wrestle Kingdom 10
Hours after the event had concluded, it was reported by multiple sources that A.J. Styles, Doc Gallows, Karl Anderson and Shinsuke Nakamura had all given their notice to NJPW on the morning of January 4, announcing that they were leaving the promotion and joining WWE. The notices reportedly led to no finishes of matches being changed by booker Gedo. The following day, the rest of Bullet Club turned on Styles, kicking him out of the stable with Kenny Omega assuming leadership of the stable. Omega was also set up as the next challenger for Shinsuke Nakamura's IWGP Intercontinental Championship. This marked Styles' final appearance for NJPW. Meanwhile, the other three were involved in angles setting up future title matches. Anderson and Nakamura remained under NJPW contracts and were expected to finish off their contracted dates with the promotion before leaving. On January 5, WWE released an article on its official website, discussing the rumors of Styles, Nakamura, Anderson and Gallows joining the promotion. The following day, Nakamura confirmed in an interview with "Tokyo Sports" that he would be leaving NJPW at the end of the month and signing with WWE. Styles officially made his WWE debut on January 24, 2016, at the Royal Rumble. Nakamura wrestled his final NJPW match on January 30, making his NXT debut two months later on April 1. The departures led to NJPW scrapping its one-year contract system and starting to offer their wrestlers multi-year contracts. In 2018, at WWE's Royal Rumble, Nakamura won the 2018 Men's Royal Rumble match to earn a World title match at WrestleMania, he chose a WWE Championship match against the champion at that time, AJ Styles (who had retained the title againest Kevin Owens and Sami Zayn earlier in the night). At WrestleMania, Styles defeated Nakamura to retain the championship. After the match, Nakamura turned heel and attacked Styles. After WrestleMania, the two continued to feud through Greatest Royal Rumble and Backlash with their matches ending in draws. At Money in the Bank, Styles retained the WWE Championship by defeating Nakamura in a Last Man Standing match, ending their feud.