Cast

Nemo: Kanta Ogaki (My Neighbor Totoro; His main attire can be for his travels in Nightmareland)

Extras with Kanta: Ash and Kaya Ketchum, Jessie, and James (Pokemon Sword and Shield; Same with Kanta for their main attires for their Nightmareland travels)

Camille: Satsuki Kusakabe (My Neighbor Totoro; Her travel clothes for Nightmareland can be the yellow sundress on the day Mei got lost, and she, the Eds, and Oak won't be trapped in reliquaries, instead, they'll partake in the final battle after Kanta's group return to Nightmareland and save them from getting fed to the Giant Spiders and their queen, and in the end, it'll be revealed that Satsuki, Mei, and Serena's true selves are new neighbors who moved into Kanta's group's neighborhood and their princesses selves were just their dream counterparts)

Extras with Satsuki: Mei Kusakabe (My Neighbor Totoro; Her travel clothes for Nightmareland can be the light pink sundress on the day she got lost) and Serena (Pokemon XYZ; Same with Satsuki and Mei on for her main attire for her Nightmareland travels)

Icarus: Pikachu (Pokemon)

Extras with Pikachu: Eevee and Meowth (Pokemon)

Flip: Ed, Double D, Eddy (Ed, Edd, n' Eddy; Eddy's addiction will be drinking coffee instead of smoking, and instead of being ordered to stop that addiction, he can instead be ordered to drink less), Megavolt, Quackerjack, Bushroot, and Liquidator (Darkwing Duck)

Flap: Jeremy (The Secret of NIMH)

Professor Genius: Professor Oak (Pokemon)

Extras who act as bodyguards for the Nightmareland travel: Chief Clancy Wiggum, Lou, Eddie, Fat Tony, Legs, Louie, Johnny Tightlips, Michael D'Amico (The Simpsons; Fat Tony's gang will be forced by Demidevimon in the shadows to persuade Kanta's group to open the Forbidden Door because Demidevimon, along with his masters, threatened to kill Michael if they didn't do it), Cloud Strife, Barret Wallace, Tifa Lockhart, Aerith Gainsborough, Red XIII/Nanaki, Yuffie Kisaragi, Cait Sith, Vincent Valentine, Cid Highwind (Final Fantasy VII), Sonic the Hedgehog, Miles "Tails" Prower, Knuckles the Echidna, Amy Rose, Cosmo the Seedrian, Tikal, Shadow the Hedgehog, Rouge the Bat, E-123 Omega, Silver the Hedgehog, Blaze the Cat, Cream the Rabbit, Cheese the Chao, Espio the Chameleon, Charmy Bee, Vector the Crocodile, Big the Cat, Froggy, Max the Wolf, Kayla the Wolf (Sonic the Hedgehog franchise), Jack Frost, North, Bunny, Tooth, and Sandy (Rise of the Guardians)

King Morpheus: Tatsuo Kusakabe (My Neighbor Totoro; He'll be the Morpheus who gets captured)

Extra with Tatsuo: Yasuko Kusakabe (My Neighbor Totoro; She'll accompany Kanta's group to save Tatsuo and the worlds)

Bon-Bon: Marlene Wallace (Final Fantasy VII)

Nemo's parents: Ignitus (The Legend of Spyro trilogy; As Ash and Kaya's dad and a human), Delia Ketchum, and Mr. Mime (Pokemon)

Boomp Goblins: The Gangreen Gang (The Powerpuff Girls (1998))

Oompo the Big Boomp: The Dazzlings (My Little Pony: Equestria Girls)

Nightmare King: Myotismon (Digimon; His monster form can be Malomyotismon, and he'll entice Kanta's group to expose their team's hiding place by torturing a voodoo doll version of Satsuki since the ones captured by the Flying Goblins will be saved by Kanta's group from the Giant Spiders and their queen)

Extras with Myotismon: Hunter J (Pokemon; As the Nightmare Queen), Vanitas (Kingdom Hearts 3; As the Nightmare Prince, who wishes to marry Serena), Negaduck, Splatter Phoenix, Taurus Bulba (Darkwing Duck/Ducktales (2017)), Demidevimon (Digimon), and Pitch Black (Rise of the Guardians; As Nightmareland's god)

Flying Goblin General: Stays the same

Black Nightmare Slime from behind the door: Stays the same

Nightmare monsters: Stays the same; Giant Spiders and their queen

Chapters

Chapter 1: Opening/Kanta's Nightmare

Chapter 2: The Circus Has Come/Invited to Slumberland

Chapter 3: Meeting the Eds and Fearsome Four/Meeting King Tatsuo and Queen Yasuko

Chapter 4: Meeting Princesses Satsuki, Mei, and Serena/A Fun Time and a Hidden Demidevimon Threatens Fat Tony's Gang

Chapter 5: Learning How to Fight Like Warrior Princes and a Warrior Princess/Causing Mischief With the Eds and Fearsome Four

Chapter 6: Kanta's Group, the Eds, Fearsome Four, Fat Tony's Gang, and Michael Open the Door/Coronation

Chapter 7: Tatsuo Captured/Returning to Slumberland

Chapter 8: Arriving in Nightmareland/Meeting the Gangreen Gang

Chapter 9: Flying Goblin Ambush/Returning to Nightmareland

Chapter 10: Rescuing the Captives From the Giant Spiders/Destroying the Spider Nest

Chapter 11: Going After Myotismon's Group/Final Battle

Chapter 12: Peace Has Returned/Ending

For gallery: Little Kanta: Adventures in Slumberland Gallery

For video game: Little Kanta: The Dream Master

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