Their contracts with Impact expired in 2022, and that same year, Anderson won NJPW's NEVER Openweight Championship, and, while still champion, he and Gallows returned to WWE in October 2022.

Allegra received a baseball scholarship to study at Mars Hill College in his home state before dropping out to pursue a wrestling career.

[8] Shortly after beginning his training under Les Thatcher in 2000, he received a concussion at the hands of fellow trainee Derek Neikirk, which put Allegra on the shelf for over a year.

[1] In the early stages on his career, he had matches with Prince Justice, Jimmy Valiant, Chris Harris, Shark Boy, and Jerry Lawler.

[12] Anderson and Ryan, now going as the Real American Heroes, successfully defend their championship on multiple occasions, but would eventually lose it to Los Luchas (Phoenix Star and Zokre) on February 10, 2008.

[13] In early 2007, Anderson debuted for Pro Wrestling Guerrilla (PWG), picking up big wins over established wrestlers such as Frankie Kazarian and Colt Cabana.

[9] On October 19, 2007, Anderson made his debut for Ring of Honor (ROH), losing to Chris Hero in a Survival of the Fittest qualifying match.

[26] As part of the new talent exchange agreement between the NWA and NJPW, Anderson replaced Yuji Nagata on March 23, 2008, in the annual New Japan Cup tournament.

[28] Anderson and Bernard entered the 2009 G1 Tag League and defeated Apollo 55 (Prince Devitt and Ryusuke Taguchi) in the final to win the tournament and earn another chance for the title.

[33] Bad Intentions made their first successful defense of the IWGP Tag Team Championship on July 19, defeating Seigigun and No Limit in a three-way "Dogfight".

[35][36] On January 4, 2011, at Wrestle Kingdom V in Tokyo Dome, Bad Intentions successfully defended the IWGP Tag Team Championship in a three–way match against Beer Money, Inc. (James Storm and Robert Roode) and Muscle Orchestra (Manabu Nakanishi and Strong Man).

[43] On September 9, Bad Intentions became the longest reigning IWGP Tag Team Champions by breaking the previous record of 446 days, set by Hiroyoshi Tenzan and Masahiro Chono in 2003.

Bad Intentions made their second GHC Tag Team Championship defense on October 31, defeating Go Shiozaki and Shuhei Taniguchi at a Pro Wrestling Noah event.

[47] On November 12 at Power Struggle, Bad Intentions made their tenth successful IWGP Tag Team Championship defense against Archer and Suzuki.

[48] On January 4, 2012, at Wrestle Kingdom VI in Tokyo Dome, Bad Intentions lost the IWGP Tag Team Championship to Tencozy (Hiroyoshi Tenzan and Satoshi Kojima), ending their record-setting reign at 564 days.

After victories over Hiroyoshi Tenzan and multi-time IWGP Heavyweight Champion Shinsuke Nakamura, arguably the biggest win of his career, he was eliminated from the tournament in the semifinals by Hiroshi Tanahashi.

After wins over Yujiro Takahashi,[61] Shiori Asahi and Kengo Mashimo, Anderson was defeated in the finals of the tournament on November 19 by Masato Tanaka.

[62] From November 20 to December 1, Anderson took part in the round-robin portion of the 2012 World Tag League, alongside Hirooki Goto under the team name "Sword & Guns".

[66] Sword & Guns received their shot at the IWGP Tag Team Championship on January 4, 2013, at Wrestle Kingdom 7 in Tokyo Dome, but were defeated in a rematch by K.E.S.

After the match, Anderson turned heel by joining Prince Devitt, Bad Luck Fale, and Tama Tonga in attacking Tanahashi.

[92] On May 17, Anderson and Gallows made their fourth successful title defense against The Briscoes (Jay and Mark) at a NJPW and ROH co-produced event, War of the Worlds, in New York City.

[96][97] On September 21 at Destruction in Kobe, Anderson and Gallows made their sixth successful title defense against Chaos' Kazuchika Okada and Yoshi-Hashi.

[102] Anderson and Gallows' year-long reign as the IWGP Tag Team Champions came to an end on January 4, 2015, at Wrestle Kingdom 9 in Tokyo Dome, where they were defeated by Goto and Shibata.

[114] On January 4, 2016, at Wrestle Kingdom 10 in Tokyo Dome, Anderson and Gallows lost the IWGP Tag Team Championship to Togi Makabe and Tomoaki Honma.

[128] After separating from Styles, Gallows and Anderson resumed feuding with The New Day, leading up to a SummerSlam match for the WWE Tag Team Championship, which they won by disqualification because of show guest Jon Stewart and a returning Big E getting involved.

On the January 1, 2018 Raw, the duo turned face by appearing as former Bullet Club stablemate Finn Bálor's surprise tag team partners.

[159] In June 2021, it was announced that Anderson along with Gallows would be returning to New Japan Pro Wrestling for the first time since early 2016 as part of the United States–based show NJPW Strong and would compete in its Tag Team Turbulence tournament.

On October 20, Anderson posted a video on his Twitter page, indicating that he would not be making his advertised commitment, with his tag team partner Doc Gallows not approving his appearance.

[2] Allegra is close friends with Fergal Devitt (now known as Finn Bálor) and Shinsuke Nakamura, whom he first met at the New Japan Pro-Wrestling dojo in Los Angeles.

[173] Allegra made his video game debut in WWE 2K17 as Karl Anderson alongside tag-team partner Luke Gallows as DLC.