Bill Simmonsmay have dubbedThe Challenge"America’s fifth sport," but the contestants on the reality competition series require decidedly less discipline than the athletes of professional sports leagues. And the psych evaluations are, to put it kindly, slightly more lax. Add a claustrophobic living situation and unlimited alcohol, and even the most mild-mannered contestants can be pushed to their emotional limits.

Psychological warfare has always been a hallmark ofThe Challenge, buta select few competitors possess toxicity that rivals Chernobyl–human disaster zones whose nuclear-level meltdowns poison the air around them and everyone in their path.The Challenge’s arsenal of characterswouldn’t be complete without a few loose cannons, and their lack of emotional regulation skills is the viewers' gain. Here are the wildest, ranked from “a few screws loose” to “escaped from Arkham Asylum.”

The Challenge

The Challenge

10Ayanna Mackins

5 Appearances

Not all loose cannons make noisy explosions. Some quietly whisper, “Jodi, I ate your Greek salad.” In her initial run onThe Challenge,Ayanna Mackinswas most known for tearfully declaring that she slept in her uniform because she wanted to win today. But whenshe made her return after a 16-year hiatusforAll Stars 2, Ayanna traded her unapologetic passion for creepy serenity reminiscent of cult members or Ralph Fiennes' portrayal of Lord Voldemort.

While recent shenanigans include monologuing for reportedly an hour in deliberation just to contradict herself in her final sentence and vote for her friend, her real pièce de résistance is Greek salad-gate. When fellow challenger Jodi asked if anyone had seen the salad she ordered, Ayanna dismissed her as acting privileged. However, Ayanna later admitted that she did knowingly take and eat Jodi’s salad and proceeded to deliver the creepiest description of a meal since Hannibal Lector enjoyed a side of fava beans and a nice Chianti.Ayanna’s active enjoyment of her cast-mates' discomfort sets her in a class of her ownamong the pantheon of loose cannons.

Ayanna Mackins screaming in celebration on the Challenge

9Abram Boise

9 Appearances

Abram Boiseis an enigma wrapped in an anomaly wrapped in a ticking time bomb. One of the most unpredictable Challengers,the audience and other contestants could never know from season to season which version of Abe was going to show up.Responsible business owner who asked to leaveThe Islandearly so that he could attend to his professional responsibilities? Hot tub threesome initiator? It was impossible to guess.

Abram was one of the most feared players in a physical challenge due to what other competitors dubbed his “crazy switch.” He even worked himself into such a frenzy beforean elimination onBloodlinesthat, ironically, he caused his own nose to bleed. For the most part, Abram reserved his more psychotic moments for the competition field onThe Challenge, but, when it comes to the guy who started the biggest fistfight inRoad Ruleshistory and smeared his feces on a jail cell wall, you can never be too careful.

Abram Boise yelling at security on The Challenge.

8Amanda Garcia

8 Appearances

With “The Devil” being one of the more charitable nicknames bestowed upon her by her fellow Challengers,Amanda Garciadoesn’t care about being popular, and she’ll ensure everyone knows it. Even for her rookie season,Rivals 3, Amanda entered the game with a massive chip on her shoulder and a willingness to go to verbal blows with even the hardened veterans,earning her status as the “Pop-off Queen.”

Behind her prickly exterior, Amanda has shown herself to be a devoted daughter to her sick father, a fierce friend, and a loving mother. But she maintains a fiery distrust toward anyone she doesn’t deem worthy of her inner circle. Amanda’s bad side is crowded, but she’s always open to making new enemies.

Amanda Garcia giving herself devil horns on ‘The Challenge’

7Laurel Stucky

Laurel Stuckyis known for beingan absolute beast on the competition field, but she’s at her most monstrous when delivering vitriolic verbal assaults. Despite her nearly 6-foot stature and icy demeanor, Laurel has never been content to merely be quietly intimidating. Since her earliest seasons, Laurel wouldn’t hesitate to unleash her fury at the smallest provocation.

For Laurel, no topic is off-limits when insulting someone into submission.Body-shaming, ageism, and–if rumors surrounding a recent episode’s argument withCara Maria Sorbelloare to be believed–domestic abuse, are all fair game in Laurel’s eyes. As arguably the least warm and fuzzy competitor onThe Challenge, the most confusing thing about Laurel may be her occupation as a veterinarian.

Laurel lounges before fighting on ‘The Challenge: All Stars 4.'

6Paulie Calafiore

WhenPaulie Calafioremade hisChallengedebut onFinal Reckoning, he quickly found himself ensnared in an old lovers’ quarrel. His flirtation withpolarizing figure Cara Mariacame with a built-in rivalry with her ex,Kyle Christie. Paulie showed no hesitation in fighting Cara Maria’s battles, and his first elimination loss of the season ended with him being escorted away by security while screaming insults at Kyle.

His short fuse continued to cause problems onWar of the Worlds 2,where,in aChallengefirst, he escalated an argument with Theo Campbell by kissing him.Paulie returned toThe Challenge: USA 2andBattle of the Erasas a seemingly reformed version of himself, but, with two early exits, it remains to be seen whether Paulie’s newfound zen would last if given more time in the pressure cooker of theChallengehouse.

5Ashley Mitchell

12 Appearances

Ashley “Millionaire” Mitchellis best known for the savage move ofstealing partner Hunter Barfield’s portionof their million-dollar prize onFinal Reckoning. But, after that ice-cold moment,Ashley is best known for her meltdowns.Even with six-figure prizes on the line, Ashley was always on a hair-pin trigger for threatening to leave the game.

While she could normally be talked out of boarding a flight back to the US–including whenJohnny “Bananas” Devenanziostole the toilet seat from her bathroom following a curry-eating challenge–Ashley showed that the bridge too far was missing luggage, which drove her to leaveDirty 30before the first challenge. But luckily for the audience, Ashley for the most part keeps her breakdowns on camera where they belong.

4Frank Sweeney

3 Appearances

Frank Sweeneybegan hisChallengecareer with a bang: WinningThe Battle of the Seasons, but not before pummeling his castmates withlow blows and unhinged verbal abuse.In addition to the constant beratement of his teammate andThe Real World: San DiegoroommateSam McGinn, Frank attacked one competitor for doing gay porn and another for her sister’s heroin addiction.

What sets Frank apart from other loose cannons is thathis capacity for toxicity seemed independent of alcohol consumption.Whereas liquor would add fuel to the fire for many erratic Challengers, Frank was a raging inferno even when sober. Nowhere was this more evident than during theBattle of the Seasonsfinal, where he mercilessly shoved and dragged an exhausted Sam up a sand dune, producing some of the worst un-punished physical abuse ever witnessed on the series.

23 Appearances

Chris “CT” Tamburellomay now be a cuddly dad with the bod to match, butoriginal recipe CT was the most feared Challenger in the game, both on and off the field.He has the distinction of being removed from the game twice for violence before a single challenge even took place, including the infamous fight onThe Duel IIwithReal World: ParisroommateAdam King, during which CT threatened to, “Smash his head and eat it.”

With his transformation into “Uncle CT” largely attributed to becoming a father and his relationship with the lateDiem Brown, CT’s 20+ years on MTV have produced one of the most fascinating character arcs in reality TV. With his brute strength, offbeat social charms, and unexpected puzzle prowess, once CT learned to control his biggest weakness–his own temper–he becameone of the undisputed greatest competitorsin the history ofThe Challenge.

2Turbo Camkiran

You don’t get a name like “Turbo” by being mindful and demure. The 2-timeSurvivor: Turkeychampion established himself as a formidable competitor when he won his rookie season,War of the Worlds, which boasted what is largely regarded as the most difficult final inThe Challengehistory. Seemingly immune to pain or discomfort, Turbo’s athletic performances often seemed beyond the capability of mere mortals.

But despite his abnormally high tolerance for physical pain, Turbo revealed himself to be quite sensitive emotionally. He was willing to escalate conflict in response to any perceived slight, even when someone wasn’t directly talking to him.The undisputed champion of taking himself too seriously,he was so distraught thatcompetitor Jordan Wiseley would mock his walkonWar of the Worlds 2, he resorted to brawling with production security, leading to his removal from the game. Considering that even CT said the man, “Scares the sh-t out of [him],” Turbo may want to consider taking up yoga or meditation.

1Camila Nakagawa

Camila Nakagawaisn’t just a loose cannon. She’s an entire arsenal of haphazardly stored explosives.Dubbed “The Camilanator,” Camila was always one tequila shot away from wreaking havoc on theChallengehouse.Also known for being a fearless competitor, Camila’s lack of forethought and concern for her own safety was ever-present both on and off the competition field.

Camila’s drunken antics frequently crossed the linebeyond lighthearted drama. A few seasons after screaming at partner Johnny Bananas that he was going to die for being a cheater, Camila got herself kicked off ofRivals 3for her increasingly escalating clashes with her partnerTony Raines. Many viewers called for Camila to be permanently exiled after a blackface incident and a racist rant directed at fellow competitorLeroy Garrett. But it wasn’t until she assaulted a crew member and stole a golf cart at the charity spin-offChamps vs Starsthat she was banned for good. Camila learned the hard way that onThe Challenge, there is no greater sin than becoming uninsurable.

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