As a human, Rupert Swaggart was a middle-aged white man with long straight red hair styled in a ponytail, a red beard, red arm hair, black eyes, light skin, and a large, plump figure. He wore a white chef's jacket with rolled up sleeves, dark blue pants, green crocs, and a grey striped scarf.
In "Cloak and Swaggart" he wears a light blue scarf.
Meat Sweats is a mutant pig with erect ears, a dark pink nose, jagged teeth, red eyes, pink skin with a light pink torso, purple cloven hooves, and a large, muscular figure, and potbelly. He has dark pink and purple markings on his arms, bumps on his skin, prominent veins, and a curly tail. His arms are a mass of tendrils. He wears a light blue waist apron with brown stains, dark blue pants, grey ankle bands, three-fingered grey gauntlets with light grey fingers, and a light grey soda jerk hat.
Meat Sweats is ill-tempered, brutal, and malicious. He has acquired a taste for Yōkai and fellow mutants and delights in quality cuisine. He takes great pride in his culinary skills and is very attentive when preparing his dishes.
Meat Sweats is deceitful, he tricks Splinter with food and socialization into entering his vehicle so that he can eat him in "The Fast and the Furriest". He seems to want his old life back as a human and will go to considerable lengths to try to obtain it.
Rupert was the owner of his restaurant Chateau Prétenche and the host of his TV show Kondescending Kitchen. However, while filming a Kondescending Kitchen episode, he was mutated into a pig by an Oozesquito due to him handling pork prior to his bite.
Meat Sweats debuted in "Donnie's Gifts", wherein the Turtles stumbled upon him harvesting some mutant silverfish in a subway. During their first fight, Meat Sweats caught Donatello and prepared to cook him. After using their inventions from Donnie to their advantage, Leonardo, Raphael, and Michelangelo fought Meat Sweats and he ended up getting thrown in front of an approaching subway train.
Meat Sweats encountered Splinter while he was in the midst of driving the Turtle Tank around New York City in "The Fast and the Furriest". He took Splinter to his Roadhouse BBQ truck to eat him where they were discovered by the Turtles who were in pursuit of Splinter. When the Turtles chased after them, he absorbed the abilities of a spitting cobra in his possession to attack. After his attack was redirected by Leo, Meat Sweats threw out Splinter and the other mutants in his possession and fled.
Sometime later in "The Evil League of Mutants", Meat Sweats was recruited into the Evil League of Mutants, a villainous group formed by Baron Draxum to kill the Turtles. Meat Sweats challenged Raph in the ensuing ambush who managed to disarm him and deliver the finishing blow against the League, bringing its defeat.
While Meat Sweats was cooking in a New York forest in his truck in "Nothing But Truffle", he was spied upon by Todd Capybara and Mikey, the latter of which wanted to learn how to properly make Meat Sweats' recipe for pork risotto. However, Meat Sweats discovered them and in turn, attempted to attack them. When Mikey was in his sights, Meat Sweats' attack was intercepted by Todd, causing him to absorb Todd's "niceness" power. As a result, Meat Sweats became kind and offered to spend the day with Mikey who enthusiastically agreed. Once their fun-filled day came to an end, the two of them returned to the forest and Meat Sweats spoke of the mystic shadow moon truffle he wished to possess. He used Mikey to aid him in traversing the forest's terrain and once they reached the tree, he asked Mikey to collect the truffle for him, withholding information involving the mystic tree's aggressive nature. It was then Meat Sweats revealed that a majority of his friendliness was merely an act as Todd's power had lost its effect on him several hours ago. Todd then made a sudden return, having uprooted the truffle before Meat Sweats had the chance to and forcefully bared his tendrils wherein Meat Sweats absorbed the mystic tree's properties. Tree Sweats pursued Todd and Mikey when they fled from him, but was soon after defeated by the same silver mallet he had gifted Mikey earlier that day.
Meat Sweats bought Sunita's stolen cloaking brooch from a vendor in the Brooch District in "Cloak and Swaggart". He used it to regain his human form and continue his old cooking show after neutralizing the new host, Guy Flambé. Sunita and April stole it back and trapped him on set of another TV show where the contestants set out to barbecue him.
In "Pizza Puffs", Meat Sweats, in an attempt to sabotage his rival's business, sold Guy Flambé poisoned pizza puffs, hoping his negligence would soil his reputation. However, he was stopped by Raph who forced him to flee the scene. Later, Meat Sweats was threatened at his New York boat home by a poisoned Leo, Donnie, and Mikey who wished to obtain the poison's antidote and he was initially able to easily fend them off. He eventually transformed into a grotesque version of himself after eating his own poisoned pizza puffs and was unable to stop the Turtles from stealing nearly all of his antidote. Meat Sweats was able to ingest the final drop after chasing after the discarded vial, relieving him of his poisoned state, but was suddenly abducted by Big Mama's mystic orb.
Meat Sweats was forced to participate in a Battle Nexus Wizbang match in "Battle Nexus: New York" to serve Amphisbaena food to soothe its hunger or else be eaten by it instead. He focused on rapidly feeding one of Amphisbaena's heads, but eventually used all of the ingredients provided to him. Meat Sweats then advised Mikey on how to spice his dish after he failed to remember how to and soon after won the match after the Yōkai ate itself. He was then teleported to the Grand Nexus Hotel and after soon abandoned the Turtles to fight Big Mama on their own.
Once a human celebrity chef, Meat Sweats is now an incredibly strong mutant pig with a menacing meat tenderizer hammer and arms made of strange tendrils that latch onto other mutants to absorb their power.
- Strength: Even without his power absorption abilities, Meat Sweats has tremendous physical strength and is quite proficient in using his meat tenderizer in combat.
- Speed: Despite his size, Meat Sweats has been shown to possess a great amount of speed.
- Power absorption: Due to his mutation, Meat Sweats can use his arm tendrils to latch onto others and siphon their essence, which causes him to temporarily gain whatever powers they possess. These are examples of his power-copying abilities:
- He gained the ability to separate himself into smaller "Mini Meats" when injured after siphoning from mutant silverfish.
- He gained the ability to spit corrosive acid after siphoning from a spitting cobra.
- He gained the ability to be hospitable and friendly after siphoning from Todd.
- He turned into a huge Were-Tree/mutant pig hybrid after siphoning from the Were-Tree. However, he was defeated when Todd threw a silver mallet at his knot hole, showing that Meat Sweats gained the Were-Tree's weakness as well.
- Culinary mastery: Meat Sweats was a professional chef and his skills were great enough to land him his own restaurant and cooking show before his mutation, skills he has retained and uses to prepare his victims into gourmet meals.
- The Mad Dogs: Meat Sweats is often in conflict with the Mad Dogs as they try to thwart his plans and he often seeks to eat them.
- Donatello: Meat Sweats captured Donnie as he was trying to flee from him in "Donnie's Gifts" with the intent to eat him. However, the inventions he gifted his brothers worked to defeat Meat Sweats and Donnie was rescued.
- Michelangelo: Mikey is big fan of Rupert Swaggart and he is a strong source of culinary inspiration to him as he is an avid watcher of Kondescending Kitchen. However, his adoration means little to Meat Sweats as he regularly tries to harm Mikey such as when he uses him in "Nothing But Truffle" in order to possess the shadow moon truffle. Later on in "Battle Nexus: New York", Meat Sweats was paired with Mikey in Big Mama's special Battle Nexus Wizbang event to feed Amphisbaena to prevent it from eating him.
- April O'Neil: Meat Sweats stole from April's friend Sunita in "Cloak and Swaggart" and she helped her take back her cloaking brooch from him.
- Raphael: Raph was the one who gave mutated Rupert Swaggart the name "Meat Sweats" after first seeing him. The two faced off in "The Evil League of Mutants", however, Meat Sweats was defeated by Raph with a weaponized ladder.
- Hamato Yoshi / Lou Jitsu / Splinter: Meat Sweats initially tried to eat Splinter in "The Fast and the Furriest", but ultimately abandoned him to face his sons' wrath when he started losing his fight against the Turtles. Meat Sweats thinks that Splinter is terrible for stealing Donnie's Turtle Tank and more immoral than even he himself is.
- Guy Flambé: Meat Sweats despises Guy Flambé as a fellow celebrity chef with around the same popularity as him. He tries to sabotage his career multiple times via violently taking over his TV show and vending him poisoned pizza puffs for Guy Flambé's customers to ruin his reputation as a chef.
- Sunita: Meat Sweats stole Sunita's cloaking brooch from her in "Cloak and Swaggart" in order to continue making Kondescending Kitchen.
- Baron Draxum: Meat Sweats was recruited as a member of Draxum's short-lived organization, the Evil League of Mutants. He questioned Draxum's motives and his background involving the Turtles during the organization's recruitment meeting. They have not been allied since.
- Todd Capybara: Meat Sweats absorbed Todd's niceness from him when he discovered that he and Mikey were spying on him in "Nothing But Truffle".
- Huginn & Muninn: Meat Sweats first met Huginn and Muninn at the Evil League of Mutants recruitment meeting in "The Evil League of Mutants", but encountered them again when they approached him in "Goyles, Goyles, Goyles" in hopes of being hired as his henchmen. Instead of employing them, Meat Sweats wished to eat them and prepared a meal to do so.
- Big Mama: Meat Sweats was abducted by Big Mama in "Pizza Puffs" and put into a match in her Battle Nexus Wizbang in "Battle Nexus: New York".
- Amphisbaena: The right head of Amphisbaena was Meat Sweat's opponent in "Battle Nexus: New York" and he worked frantically to feed it with much success. He was able to win the match after the Yōkai ate itself in its ravenous hunger.
- "Oh, that's too much flavor." ("The Evil League of Mutants")
- "I'm done with you, TGI Parmesan. No meal is worth this!" ("The Fast and the Furriest")
- "Oh, no! What's happening to this little piggy?" ("Pizza Puffs")
- Rupert's show, Kondescending Kitchen, is a parody of Gordon Ramsay's Hell's Kitchen.
- Meat Sweats is voiced by John Lydon, better known as Johnny Rotten.
- Meat Sweats' catchphrase is "Unleash the flavor".
- His catchphrase ordinates from Kondescending Kitchen.
- According to his bio, Meat Sweats can literally sweat meat.