Adam & Steve: Adam voted for Steve to compete in the first elimination round of The Challenge: All Stars 4. Later in the season, after winning the "Shish Kestack" Arena, Steve opted to steal Adam's Star as a result of this decision.[3]
Devin & Leroy: After Devin was voted into the elimination round on The Challenge: Double Agents, Leroy selected Devin's ally Wes Bergmann to be his opponent.[4]
Female/male teams
Amber & Faysal: Faysal and Amber first clashed in a shaky Big Brother alliance on The Challenge: Double Agents. Faysal then blindsided Amber to go into the elimination round on The Challenge: Spies, Lies & Allies.[5]
Ashley K. & Dario: The two are exes. They first met on The Challenge: Invasion of the Champions and later started dating. They have not spoken to one another in six years.[1]
Big T & Corey: The two had a falling out after Corey claimed he was using game information from Big T against her, and she became the main target on The Challenge: Battle for a New Champion. She felt their personal relationship was affected by this cold reveal and did not fully accept his apology at the reunion.[6]
Da'Vonne & Shane: Da'Vonne and Shane fought on The Challenge: Final Reckoning after Shane threw the "Don't Push Me Around" challenge, thus causing Da'Vonne and her partner Jozea Flores to be voted into the elimination round, which they ultimately lost. This was preceded by an earlier vote where Shane felt Da'Vonne went against her word and during an argument verbally accosted her.[7]
Frank & Sam: The two former The Real World: San Diego roommates competed together on The Challenge: Battle of the Seasons, where they ultimately won. Frank did not consider Sam a worthy teammate and physically pushed her through the finish line during the Final Challenge.[8]
Nany & Turbo: On The Challenge: War of the Worlds Turbo picked Nany to be his partner. On The Challenge: Ride or Dies, the two had a falling out and Johnny "Bananas" Devenanzio and Nany ultimately selected Turbo and his partner Tamara Alfaro for the elimination round.[9]
Female teams
Aneesa & Ashley M.: Aneesa talked poorly about Ashley at a Challenge-related fan event.[1]
Beth & Jonna: Entering The Challenge: All Stars 3, Beth did not trust Jonna and implied she was cheating on her husband with MJ Garrett. Jonna was eventually voted in elimination and called out Beth as her opponent. However, Beth withdrew midway through the "Knock Off" elimination since her opponent was receiving help from MJ.[10]
Katie & Veronica: The two were teammates on both Real World/Road Rules Challenge: The Gauntlet and Real World/Road Rules Challenge: The Inferno. On both seasons, Katie was perceived as the Road Rules team's weak link. After being selected for The Inferno twice by the opposing team, Veronica won the Aztec Life Saver and sent Katie in to replace her both times. Katie won both elimination rounds and ultimately was part of the winning team alongside Veronica.[11][12]
KellyAnne & Sylvia: On The Challenge: All Stars 3, Sylvia used her first sabotage on KellyAnne. Later in the season, KellyAnne selected Sylvia to go into the elimination which she ultimately lost.[13]
Melissa & Nicole: They hooked up on The Challenge: Vendettas. They remained friends until Melissa became friends with Nicole's ex, Laurel.[14][1]
