[8] O'Reilly appeared at NWA: Extreme Canadian Championship Wrestling (ECCW)'s television tapings on December 23, 2005, where he and Tony Tisoy lost to Wrathchild and Killswitch.

[9] In January 2006, O'Reilly was in the main event of ECCW's tenth anniversary show, teaming with Fast Freddy Funk and Kurt Sterling to defeat Michelle Starr, Johnny Canuck and Vance Nevada.

[17] At To Hell and Back on June 25, O'Reilly wrestled twice in one night, defeating Ice before losing to Sylum in a match for the NWA Canadian Heavyweight Championship.

[48] O'Reilly made his ROH pay-per-view debut on December 18 at Final Battle 2010, where he and Cole were defeated by the All Night Express (Rhett Titus and Kenny King).

[49] On April 1 and 2 at Chapter One and Two of Honor Takes Center Stage, O'Reilly and Cole faced The Briscoe Brothers (Jay and Mark) and The Kings of Wrestling (Chris Hero and Claudio Castagnoli) in two losing efforts, despite putting on strong performances.

[59] On December 16 at Final Battle 2012: Doomsday, O'Reilly and Bobby Fish (known as reDRagon) faced the reformed The American Wolves (Davey Richards and Eddie Edwards) in a losing effort.

[61] The same month, they successfully defended the championship against Alabama Attitude (Corey Hollis and Mike Posey), before retaining it at Best in the World 2013 in June in a three-way match against the C & C Wrestle Factory (Caprice Coleman and Cedric Alexander) and S.C.U.M.

[64][65] Over the next several months reDRagon successfully defended the championship against teams including the C & C Wrestle Factory, the Forever Hooligans, and Jay Lethal and Michael Elgin.

[66][67] They retained the championship against Outlaw, Inc. (Homicide and Eddie Kingston) at Final Battle 2013 in December and Adrenaline Rush (A. C. H. and TaDarius Thomas) at the 12th Anniversary Show in February 2014.

[70] ReDRagon regained the tag team championship from The Young Bucks on May 17, at the ROH and New Japan Pro-Wrestling (NJPW) co-promoted pay-per-view War of the Worlds.

[74] They followed up their victory with successful title defenses against the Time Splitters (Alex Shelley and Kushida) at Final Battle 2014, The Young Bucks in March 2015 at ROH's 13th Anniversary Show, and The Kingdom (Michael Bennett and Matt Taven) at Supercard of Honor IX.

[79] On August 19, 2016, at Death Before Dishonor XIV, O'Reilly made his return and surprisingly interrupting Cole's victory celebration as the two-time ROH World Champion by attacking him, thus reigniting their feud.

[84] On October 22, 2011, O'Reilly debuted in Pro Wrestling Guerrilla alongside regular tag team partner Adam Cole as Future Shock.

After defeating the DojoBros (Eddie Edwards and Roderick Strong) in their first round match, the team was eliminated from the tournament in the semifinals by El Generico and Kevin Steen.

[94] In August, O'Reilly made it to the semifinals of the 2014 Battle of Los Angeles, but was forced to withdraw from the match after suffering a storyline injury at the hands of Roderick Strong.

[95] On December 12, O'Reilly successfully defended the PWG World Championship against the 2014 Battle of Los Angeles winner Ricochet, only to lose it to Strong in an impromptu Guerrilla Warfare match immediately afterward.

Through ROH's relationship with NJPW, reDRagon made an appearance for the Japanese promotion on August 10, unsuccessfully challenging Time Splitters (Alex Shelley and Kushida) for the IWGP Junior Heavyweight Tag Team Championship.

[100] They made their first successful title defense on January 4, 2015, at Wrestle Kingdom 9 in Tokyo Dome, in a four-way match against Forever Hooligans, Time Splitters and The Young Bucks.

[102][103] reDRagon returned to NJPW on May 3 at Wrestling Dontaku 2015, where they unsuccessfully challenged for the IWGP Junior Heavyweight Tag Team Championship in a three-way match with Roppongi Vice (Beretta and Rocky Romero) and The Young Bucks.

[107] Following the tournament, reDRagon received a rematch for the IWGP Junior Heavyweight Tag Team Championship in a three-way match, also involving Roppongi Vice, but were again defeated by The Young Bucks on July 5 at Dominion 7.5 in Osaka-jo Hall.

[109] They lost the title back to The Young Bucks in a four-way match that also included Roppongi Vice and Matt Sydal and Ricochet on January 4, 2016, at Wrestle Kingdom 10 in Tokyo Dome.

[110] On October 10 at King of Pro-Wrestling, O'Reilly received his first singles title shot in NJPW, when he unsuccessfully challenged Katsuyori Shibata for the NEVER Openweight Championship.

They then attacked newly crowned NXT Champion Drew McIntyre later that night, being joined by the debuting Adam Cole, turning heel in the process.

On the November 8 episode of NXT, O'Reilly and Fish interrupted Roderick Strong vs. Adam Cole, leading to a massive brawl among the WarGames teams.

At TakeOver: WarGames, The Undisputed Era defeated SAnitY and the team of Roderick Strong and The Authors Of Pain to win the first War Games match that was held in over 17 years.

On the June 19 tapings for the second annual United Kingdom Championship Tournament, O'Reilly and Strong lost the titles to Moustache Mountain (Tyler Bate and Trent Seven), but won them back two days later.

[121] After the event, O'Reilly and the rest of The Undisputed Era would begin to feud with The Kings of NXT (Pat McAfee, Pete Dunne, Danny Burch, and Oney Lorcan).

At NXT TakeOver: Vengeance Day, The Undisputed Era aided Finn Bálor to fend off Pete Dunne, Danny Burch, and Oney Lorcan.

[132] After his feud with Cole ended, O'Reilly would form an uneasy partnership with newcomer Von Wagner, who helped him fend off an attack from Pete Dunne and Ridge Holland.

[6] Growing up, Greenwood participated in several sports, including amateur wrestling, ice hockey, football, lacrosse, kickboxing, Jiu-jitsu, and snowboarding, and briefly played rugby in Europe.