DLC Roster guesses for Slime Speedway
- Aaahh!!! Real Monsters: Ickis, Krumm, Zimbo
- The Angry Beavers: Norbert, Daggett
- Avatar: The Last Airbender: Katara, Sokka, Azula
- Back at the Barnyard: Otis, Pig
- The Backyardigans: Pablo, Tyrone, Uniqua, Tasha, Austin
- Big Nate: Nate, Francis, Teddy
- Blue's Clues: Steve, Joe, Blue, Magenta
- Blue's Clues & You!: Josh
- Breadwinners: Buhdeuce, Sway-Sway, Ketta
- CatDog: Winslow, Rancid Rabbit
- Catscratch: Mr. Blik, Waffle, Gordon
- ChalkZone: Rudy, Snap
- Danny Phantom: Vlad Plasmius, Dani Phantom, Ember McLain
- Dora the Explorer: Dora, Boots, Diego, Swiper
- Double Dare (1986): Marc Summers
- Doug: Doug Funnie, Porkchop, Roger Klotz
- El Tigre: The Adventures of Manny Rivera: Manny Rivera, Frida Suarez
- The Fairly OddParents!: Timmy Turner, Cosmo, Wanda, Vicky, Mr. Crocker
- Fanboy and Chum Chum: Fanboy, Chum Chum, Kyle, Boog
- Garfield: Jon Arbuckle
- U.S. Acres: Orson, Roy, Wade
- Glitch Techs: Five, Miko
- Gullah Gullah Island: Binyah Binyah Polliwog
- Harvey Beaks: Harvey, Fee, Foo
- iCarly: Carly Shay, Gibby
- Invader Zim: Dib, Gaz, Mini Moose
- It's Pony: Annie (either by herself or as The Dividual with Pony)
- Jimmy Neutron: Boy Genius: Carl, Sheen, Hugh, Professor Calamitous
- Planet Sheen: Nesmith, Dorkus
- KaBlam!: Henry, June, Loopy
- Kenan & Kel: Kenan Thompson, Kel Mitchell
- Kung Fu Panda: Legends of Awesomeness: Po, Tigress, Shifu
- Legends of the Hidden Temple: Kirk Fogg, The Silver Monkey (as this game's answer to the Iron Checkpoint Crate)
- The Loud House: Lynn Jr., Luna, Luan, Lori, Leni, Lola, Lana, Lisa, Ronnie Anne, Morag
- The Mighty B!: Bessie
- Monsters vs. Aliens (2013): B.O.B., Link, Sqweep
- Noggin: Moose A. Moose, Feetface
- The Penguins of Madagascar: Skipper, Private, Kowalski, Rico, King Julien, Marlene
- Rocket Power: Reggie, Otto, Twister, Sam, Ray, Tito
- Rocko's Modern Life: Heffer, Filburt, Rachel Bighead
- Rugrats: Tommy, Angelica, Phil, Lil, Dil, Kimi, Stu, Didi, Drew, Lou, "Not Tommy"
- All Grown Up!: An aged-up version of one of the babies
- Sanjay and Craig: Sanjay and/or Craig, Tufflips
- SpongeBob SquarePants: Mr. Krabs, Plankton, Larry the Lobster, the Flying Dutchman, Abrasive SpongeBob
- Kamp Koral: Kamper Sandy, Kamp Kounselor Squidward, Narlene, Nobby
- The Patrick Star Show: Hawaiian Shirt Patrick
- Tak and the Power of Juju: Tak, Lok, Jibolba, Tlaloc
- Teenage Mutant Ninja Turtles: A 2003, 2007, 2012, or Rise iteration of one of the Turtles, Shredder
- Transformers: EarthSpark: Optimus Prime, Bumblebee, Megatron
- T.U.F.F. Puppy: Dudley Puppy, Kitty Katswell
- The Wild Thornberrys: Eliza, Nigel, Darwin
- The X's: Mr. X, Mrs. X, Tuesday X, Truman X
DLC track guesses for Slime Speedway
- All That: All That Studio
- The Angry Beavers: Beaver Dam
- Back at the Barnyard: Club Otis
- Blue's Clues: Blue's Room
- Catscratch: Cramdilly Mansion
- ChalkZone: ChalkZone
- Dora the Explorer: Amazon River Rapids
- The Fairly OddParents!: Fairy World
- Fanboy and Chum Chum: The Fanlair
- iCarly: iCarly Studio
- Legends of the Hidden Temple: The Hidden Temple
- The Loud House: The Loud House, Loch Loud
- The Mighty B!: Pier 31
- Monsters vs. Aliens (2013): Area 52
- Nickelodeon GUTS: The Aggro Crag
- The Penguins of Madagascar: Central Park Zoo
- Rocket Power: MadTown
- Tak and the Power of Juju: Dryrock Canyon
- T.U.F.F. Puppy: TUFF Headquarters
- The Wild Thornberrys: Rumble in the Jungle
- The X's: Homebase
- A recreation of Nickelodeon Studios at Universal Studios
DLC kart/bike guesses for Slime Speedway
- The Angry Beavers: A kart modeled after Stump
- Breadwinners: The Rocket Van
- Catscratch: Gear
- The Fairly OddParents!: SuperBike
- Hey Arnold!: The Mauve Storm
- It's Pony: Pony
- Jimmy Neutron: Boy Genius: Strato XL
- Legends of the Hidden Temple: A kart modeled after Olmec
- Nickelodeon GUTS: A kart modeled after the pieces of the Aggro Crag
- Nicktoons Racing: The Mystery Racer's kart
- The Mighty B!: A swarm of bees flying in a formation vaguely resembling a kart, carrying the driver and the miscellaneous parts of the "vehicle"
- The Penguins of Madagascar: Safari Jeep
- SpongeBob SquarePants: The Invisible Boatmobile, Karen
- The Wild Thornberrys: The ComVee
JoJo Siwa was deliberately kept The Voiceless in Slime Speedway as a secret way for the devs to tell players that they were forced to include her, and to discourage players from playing as her so that she often won't appear in races.
