In 2005, Reso departed WWE and signed with Total Nonstop Action Wrestling (TNA) under his Christian Cage ring name, after which, he won the NWA World Heavyweight Championship twice.

[3] Christian made his television debut as a heel at WWF's pay-per-view event Breakdown: In Your House on September 27, distracting Edge during his match against Owen Hart to reveal his allegiance to Gangrel.

The next night on Raw Is War, The Hardy Boyz dressed as the Los Conquistadores and defeated Edge in a handicap match after Christian was taken out backstage to regain the WWF Tag Team Championship.

[25][26] At No Way Out on February 25, Edge and Christian were unsuccessful in regaining the tag team titles,[27] but they eventually recaptured them in the second ever TLC match at WrestleMania X-Seven on April 1.

[3] Christian began throwing tantrums in his gimmick at the time whenever things did not go his way and during the same event defeated Mighty Molly to win the WWF Hardcore Championship, but lost the title to Maven later that night.

[citation needed] After a short absence, Christian returned on the April 7 episode of Raw, self-proclaiming himself as the new "People's Champion" and began calling his fans "The Peeps" after receiving advice and endorsement from The Rock.

[51] During a steel cage match against Jericho on the May 10 episode of Raw which he lost, Christian suffered a severe back injury, causing him to miss almost four months of in-ring action.

At New Year's Revolution on January 9, 2005, Christian and Tyson Tomko faced Eugene and William Regal for the World Tag Team Championship, but they failed to win the titles.

[63] He announced his intentions to win the NWA World Heavyweight Championship held by Jeff Jarrett and rejected joining Scott D'Amore's faction, Team Canada.

[71] At Slammiversary on June 18, Cage lost the NWA World Heavyweight Championship to Jeff Jarrett in a King of the Mountain match, which also involved Abyss, Ron Killings and Sting.

[104] The two had a rematch with Matt Morgan as the special outside enforcer at Bound for Glory on October 14, where Cage lost to Joe and ended his 23-month-long undefeated streak by not officially being pinned nor made to submit.

[105] Cage and Joe fought one more time on the October 18 episode of Impact!, with a spot in the 2007 Fight for the Right tournament to become number one contender to the TNA World Heavyweight Championship.

[108] Later in the night, Styles and Tomko helped Angle retain the TNA World Heavyweight Championship during the main event as Cage looked on from the ramp.

[119] Cage was involved in a three-way match for the TNA World Heavyweight Championship against the champion Samoa Joe and Kurt Angle at No Surrender on September 13, but he failed to win the title.

[129] Christian won a tri-branded 15-man battle royal on the March 10 episode of ECW,[130] gaining entry into the Money in the Bank ladder match at WrestleMania 25 on April 5, which he failed to win.

[134] At Extreme Rules on June 7, Christian lost the ECW Championship to Tommy Dreamer in a triple threat hardcore match also involving Swagger.

[139] Christian then began a rivalry with William Regal over the ECW Championship, retaining the title against him at SummerSlam in eight seconds on August 23,[140] and at Breaking Point on September 13.

[159] On the March 7 episode of Raw, Christian made his in-ring return from injury against Del Rio's bodyguard Brodus Clay, picking up the victory.

[163] On the April 8 episode of SmackDown, Christian lost to Del Rio in a number one contender's match for the World Heavyweight Championship after a distraction from Brodus Clay.

[166] On the May 6 episode of SmackDown, Christian lost the World Heavyweight Championship to Randy Orton ending his reign at 2 days (5 recognized by WWE due to tape delay).

[169] At Capitol Punishment on June 19, Christian faced Orton for the World Heavyweight Championship once again, but he failed to capture the title as the referee missed his foot under the bottom rope.

[183] Christian made his return at Over the Limit on May 20, as a face, where he won a battle royal and defeated Cody Rhodes later in the show to win his fourth Intercontinental Championship.

[189] That same week on SmackDown, Christian defeated Randy Orton and Rob Van Dam in a triple threat match to become number one contender to the World Heavyweight Championship, after which he was attacked by Del Rio during a post-match interview.

[199][200] After suffering his concussion, Christian appeared as a face on pre-show discussion panels for WWE for events including NXT TakeOver, Money in the Bank and Battleground.

[206] Pro Wrestling Insider corroborated Lawler's statement, adding that because of multiple concussions and other injuries, the company considered Christian retired as an active wrestler.

[212] At the Raw 25 Years event on January 22, 2018, Christian hosted The Peep Show with special guests Jason Jordan and Seth Rollins, but it was later interrupted by The Bar (Cesaro and Sheamus).

[215] On the June 8, 2020 episode of Raw, Christian hosted The Peep Show with special guest Edge, who had returned to competition in January and was feuding with Randy Orton.

He is literally doing some of the best work of his career, and he is currently one of the most entertaining things on either Collision OR Dynamite... A lot of younger heels really need to take the time to study what Christian is doing and replicate it in their own ways."

[258] On August 25 at All In, The Patriarchy lost the AEW World Trios Championship in a four-way London ladder match to Pac and Blackpool Combat Club (Claudio Castagnoli and Wheeler Yuta), ending their reign at 37 days.

[272] In 2007, TNA Home Video released a DVD titled The Instant Classic: Christian Cage, covering his beginnings in the independent circuit and other various subjects up to his second NWA World Heavyweight Championship reign.