Mike is the main personality. Mike is somewhat shy and fearful of having the truth of his multiple personality disorder being revealed. Due to his other personalities, he has little knowledge of what they do and sometimes their outcome can be harmful to Mike's regular life like his relationship with Zoey. As of The Final Wreck-ening Mike is permanently cured.
The four personalities serve as the supporting antagonists in Season 4 and later, the tritagonists in Season 5, while Mal, the evil one, is the main antagonist of the season.
Chester is the first personality seen on Total Drama: Revenge of the Island. He debuted in Bigger! Badder! Brutal-er! when the team was trying to cut down the totem pole. Chester is a grumpy old man who has a hunched back, a wrinkled face, one eye shut, and complains about the youth of today.
Chester was also seen in Truth or Laser Shark. While he was sleeping, he began fussing over the youth and going back and forth from Chester to Mike. Chester appeared when Mike was accidentally hit with a spoon in Ice Ice Baby. He was annoyed and said people used to eat with their hands. In Backstabbers Ahoy!, Chester is shown in the beginning of the episode while Mike is asleep saying how his other personalities are "punks."
In Runaway Model, Chester appears and complains that Anne Maria and Zoey were making Jo's make-up too complicated, and that they just needed to "add a bit of rouge." He proceeded to apply the make-up on her himself, but ended up making Jo unbelievably ugly. Jo later found out and threw barrels at Mike, while calling him Chester, to which Mike had no idea of what he had done.
Chester also makes a few appearances in The Treasure Island of Dr. McLean. First he appears in a flashback where it's explained that Mike turns into Chester whenever he gets frustrated Mike stubs his foot on a rock, causing him to change into Chester and kick the rock, which just hurts him more. The second time is when the Mutant Maggots are rowing back to shore, and the team falls into disarray, frustrating Mike to the point of turning into Chester.
Chester appears in the confessional in Grand Chef Auto. He is skeptical that Zoey will not think they are weird.
Svetlana is a Russian gymnast that debuts in Truth or Laser Shark. Speaking in a Russian accent and in third person, she has: long eyelashes, thick lips, and a graceful figure. She appears proud and confident in her skills whenever she appears. Jo compliments her on her athletic skills. Svetlana is Mike's only female alternate personality and has unique eye irises. Svetlana also appears in the theme song, performing acrobatics in front of Zoey. She first appears during the second challenge of Truth or Laser Shark. When Mike starts giving himself a pep talk, he changes to Svetlana, who finishes Mike's part of the relay with ease. In Ice Ice Baby, Cameron purposefully tries to get Mike to change to Svetlana because of her great athletic skill by calling her up to perform. It works, and Svetlana launches herself towards the Rats' fortress.
In Finders Creepers, Mike changes to Svetlana in order to save the other contestants from the spider.
Svetlana makes a brief appearance in The Treasure Island of Dr. McLean, first time being in a flashback, and the second being when Mike is climbing a tree, and begins struggling. After landing, with perfect form, he changes back to Mike in order to rescue Zoey.
Svetlana admits that she does not want Mike to be the boss of the body in Grand Chef Auto.
In Saving Private Leechball, Svetlana is the alternate personality that Sierra likes best.
Vito is a tough and aggressive man that debuts in Ice Ice Baby. He seems to enjoy picking fights and flirting. Vito also seems a little clueless and lazy at times as seen in Finders Creepers.
This personality likes Anne Maria, as shown throughout the show. He is muscular, usually shirtless, and has hair that is gelled back. Vito, just like Anne Maria, is based on the Jersey stereotype. This attraction is disapproved of by Mike and has subsequently caused a love triangle between himself, Zoey, and Anne Maria. The first mention of Vito was in Anne Maria's Total Drama Online biography, where she mentioned that her dream date would be with Vito. Mike is shown to not like Vito because he is harder to control than Svetlana and Chester. Unlike the actual scenario, Anne Maria believes Vito is the real personality and Mike is the real "act." Whenever, Vito appears "Duncan's theme" is played.
Vito appeared in Grand Chef Auto when Scott ripped off Mike's shirt. Vito wanted to know where Anne Maria was and Scott promised to take him to her.
- Anne Maria
Manitoba Smith makes his first appearance in A Mine Is a Terrible Thing to Waste. He has a thick Australian accent and is able to track what is nearby just by observing the ground. He is fairly cocky and quick to take charge, but is also quite funny. He is hinted to be rather sexist, saying that the mine carts would be too dangerous for girls, which noticeably upset both Zoey and Anne Maria. This personality is triggered by him wearing a fedora. His next appearance was a brief one at the beginning of The Treasure Island of Dr. McLean when Mike puts on a fedora. However, Cameron quickly removes the hat, changing Mike back to his normal self. He is a parody of Indiana Jones, although his accent parodies both "Crocodile" Dundee and the late Steve Irwin.
Manitoba lassos Mike in Grand Chef Auto and says that Mike gets in the way of his flirting.
In Evil Dread, Cameron got Mike to turn into Manitoba Smith for Manitoba Smith's digging skills by placing a hat on Mike's head.Manitoba sees that Scott is trying to cheat by placing The heroic hamster's piece on their side and takes the piece. Scott steps back triggering a bee hive booby trap and hits Manitoba as he runs off. Manitoba is sent back into Mike's subconscious and senses the presence of the Malevolent One. As the other alternate personalities scream in fear, a giant picture of Mike is transformed into a black silhouette of the Malevolent One.
In The Final Wreck-ening, Mike and with his personalities all pressed the reset button at the same time in his mind to blow up Mal's tower and his personalities removed.
- Anne Maria
Total Drama Presents: The Ridonculous Race