On November 8 at Power Struggle, Styles defeated Yoshitatsu with help from Jarrett and after the match was confronted by Tetsuya Naito. During the match, Yoshitatsu legitimately broke his neck on a botched "Styles Clash" in which he tucked his head, leading to NJPW pushing Styles as a "killer" and the "Styles Clash" as a controversial maneuver. Later in the month, Styles entered the 2014 World Tag League, alongside Yujiro Takahashi. Despite a win over the reigning IWGP Tag Team Champions, Bullet Club stablemates Doc Gallows and Karl Anderson, Styles and Takahashi failed to advance from their block with a record of four wins and three losses due to losing to Kazuchika Okada and Yoshi-Hashi on the final day. Styles and Naito faced off in a match on January 4, 2015 at Wrestle Kingdom 9 in Tokyo Dome, where Styles was victorious. On January 6, 2015, Styles inserted himself back into the IWGP Heavyweight Championship picture, when he pinned Tanahashi in an eight-man tag team match, setting up a title match between the two at The New Beginning in Osaka. On February 11, Styles defeated Tanahashi to win the IWGP Heavyweight Championship for the second time. Styles made his first title defense on April 5 at Invasion Attack, where he defeated 2015 New Japan Cup winner Kota Ibushi. His five-month reign ended in his second defense on July 5 at Dominion 7.5 in Osaka-jo Hall, where he was defeated by Kazuchika Okada. From July 20 to August 14, Styles took part in the 2015 G1 Climax. Styles entered the final day with a chance to advance from his block, but a loss against Hiroshi Tanahashi cost him a spot in the finals, giving him a record of six wins and three losses. On October 12 at King of Pro-Wrestling, Styles received a rematch for the IWGP Heavyweight Championship, but was again defeated by Okada.