[5] After being denied a place in the All Japan dojo, Ishii instead began training with DDT, and made his debut on July 6, 2008, unsuccessfully challenging Daichi Kakimoto for the World Ōmori Championship.

[8] In September, Ishii took part in the Young Drama Cup, winning his block with 7 points and advancing to the final, where he once again defeated Sasaki.

[10] Ishii took part in the 2010 King Of DDT tournament, defeating Tanomusaku Toba in the first round[11] and Yago Azanable in the second,[12] but lost to Harashima in the semi-finals.

[12] On June 13, Ishii teamed with Hikaru Sato and Yoshihiko to defeat Tokyo Gurentai (Nosawa, Mazada and Fujita) and win the UWA World Trios Championship.

[13] They lost the championships on July 25 in a triple threat match also featuring Kudo, Antonio Honda and Yasu Urano, as well as winners Great Kojika, Mr. #6 and Riho.

[28] On November 13, Ishii captured the DDT Extreme Championship at a Union Pro event, defeating Shuji Ishikawa in a lumberjack deathmatch.

[35] Ishii and Takao became #1 contenders to the KO-D Tag Team Championship on August 18, but were unable to defeat champions Isami Kodaka and Yuko Miyamoto on September 29.

Ishii entered the tournament to crown the new champions on July 23 alongside Dino and Super Sasadango Machine, but was eliminated in the first round by New Wrestling Aidoru (Katsumata, Mao and Oishi).

[50] In 2007, Ishii took part in a public tryout held by Keiji Mutoh, where the people who passed would be considered for a place in the AJPW dojo.

[4] In late 2013, Ishii returned to AJPW, and on October 27 unsuccessfully challenged Burning (Kotaro Suzuki and Atsushi Aoki) for the All Asia Tag Team Championship alongside Irie.

[55] In October, Ishii and Takao took part in the 2014 Junior Tag Battle Of Glory tournament, making it the playoffs where they were eliminated by Evolution (Aoki and Hikaru Sato).