(Dawn of the Second Day)
(48 hours remain)
(Mitsuri's House)

The next day, the group received hot cakes prepared by Mitsuri Kanroji, wearing an apron.

"Pancake is a thin, flat cake of batter, usually fried and turned in a pan. It usually eaten with syrup or rolled up with a filling." Cancer said before talking to Kanroji. "I didn't know you could make western sweets, I see they were prepared with love and they are delicious."

"Thank you." Mitsuri said, feeling flattered.

"First this breakfast, and then the plan to defeat Muzan and the other demons will start." Sara said.

(Ubuyashiki Mansion)
The group was gathered with the Pillars/Hashiras.

"I have discovered this." Caleb said before showing it to the Zodiacs and Elementals a book showing a luminous yellow butterfly-shaped flower. "It's the Luminous Butterflower and says that it can extend the life of the people after 25 years of age who awake the Demon Slayer marks, only appearing in the forests of the Aether Kingdom, I must find them."

"Wow." Zodiacs, Elementals and other children said in amazement.

"With that we will have more years of life after battle." Gyomei said.

"Okay, the arrow of 50 liters of wisteria mixed with other poisonous plants is ready and also has a sample of Shinobu's blood." Seth said as he spoke with the Wood Elemental. "Some of us will fight against Doma and then when he is distracted, you launch the arrow to poison him."

"Got it." Keith M nodded.

"Now let's speak about the next upper moons." Seth said.

"Kokushibo, before being transformed into a demon, his name was Michikatsu Tsugikuni, a Demon Slayer formerly." Caleb explained before turning to see the capricorn warrior and Light Elemental. "Okay, Aaron and Capricorn, I'll need you two to face Kokushibo, you'll need to turn him back into a human, but also give the Butterflower elixir to heal him."

"We would do it." Capricorn said..

"Leave it to us." Aaron said.

"The third upper moon is Revlis, the first hybrid demon, created with Silver's DNA and DNA from their Pokémon, clearly a replacement for Akaza after he destroyed himself." Caleb said.

"We'll face that hybrid abomination!" Ash said.

"Us too!" Koji and Koichi said in unison.

"The fourth upper moon is Nakime, the one who controls the Infinity Castle, but she must be beheaded off until the right moment because when she dies, the Infinity Castle will collapse." Aries explained.

"Understood." Obanai nodded.

"The fifth one is unknown yet but the sixth one is Kaigaku." Jigoro said before explaining. "When I discovered it I tried to kill me but the love of Zenitsu and Nezuko warmed my heart and therefore I want to see my honorary nephew to keep living."

Outside of the reunion's room, Zenitsu heard everything and then he got serious before going outside to train seriously knowing that the right moment had come.

"I think I saw the fifth upper moon after Gyokko's death, his name is Adam Crowley." Seth said.

"Adam Crowley from Nightmare Creatures!?" Aries said in surprise.

"Wow!" DK said.

"Damn…!" Takeda said.

"Oh my god!" Magolor exclaimed.

"Holy crap!" Luke added.

"I didn't see that coming, the foreigner's first upper moon." Aries said.

"He is responsible for creating the hybrid demons, including elemental variants too." Seth said before adding. "And also Muzan used Pureblood Heartless to create dark clones of the demons who were defeated previously, no heart, no soul, no memories from their tragic human lives and they are twice stronger than the original ones."

"Oh boy…" Aidan and the rest of the Elemental 10 rolled their eyes in annoyment.

"Since when did you know all that info?" Lunamon asked Seth.

"While me and Coronamon were double agents, I offered myself to find the Blue Spider Lily during the day, I searched the plant everywhere but I hadn't luck, even Muzan understood my effort but he changed his plans when he discovered Nezuko is immune to the sun and he wants to become immortal, that explained why he wanted to find the Blue Spider Lily or creating a demon immune to the sun." Seth explained and the whole group was shocked by the information, minus Aries, however before he could speak.

"Nezuko must be moved to a safe place, far away from Muzan, with Urokodaki." Giyu said.

"I'll come to Urokodaki's house too." Jigoro said.

"Now if you excuse me, I'm going to find the Luminous Butterfly." Caleb said before getting up and exited from the reunion's room.

"Capricorn, before facing the upper moons, first use a spell to nullify Nakime's Blood Demon Art." Aries whispered in Capricorn's ear and he nodded.

(Aether Kingdom: Mountains)
Then Caleb teleported there and went inside the cave, he continued until arriving at the Crystal Forest and after passing said place he found a cave full of shiny moss and then he found the yellow luminous butterfly-shaped flowers.
"I found them!" Caleb said before collecting the necessary number of plants. "Now it's time to train!"

(Taisho Period: Training Grounds)
Caleb returned back to the Taisho Period with the Luminous Butterflowers.

*Hidden Skill Training (from LOZ: Twilight Princess)*

Tanjiro wanted to erase the memories when he found his family murdered, however even if his family was revived, Muzan and the demons with his blood haunted Tanjiro's previous bloodline across many years and he must be the one who ends this torment for years.

Aries trained with his improved guns and also practiced the Sheep Spirit battle style, Taurus was practicing with the Blade of Hope, Gemini with the blades attached to her shoe soles, Cancer with her sharpened twin boomerangs, a shirtless Leo is practicing with the shield and sword and even swinging his shield to block and deflect the attacks (like in LOZ: Breath of the Wild), Libra is practicing with her scale-like scepter and rapier, Virgo is practicing with her magic gauntlets and boots, Scorpio with his twin scythe, Capricorn with his magic tome to use elemental spells, Sagittarius with his broadsword, Aquarius with his new armor, Pisces is practicing with sculpture to create living sculpture for the battle.

A shirtless Aidan is practicing with his fire broadsword and Dragon Gauntlet which first he sent 3 slash projectiles (like Volga in Hyrule Warriors), performing a ramming attack but with dragon wings made of fire, even Glaive Rush, Dragon Rush, Dragon Arrows which fires dragon arrowheads from his gauntlet, Dragon Claw, Dragon Laser (based from Pokémon Flickle Beam), Dragon Hammer, Dragon Pulse and Aidan charged forwards while leaving a trail of flames in his wake (based from Volga's Special Attack), Assana is practicing with her Aqua Lasso and performed her skills (from Kirby's Whip Splash), Skye has equipped Winged Boots and practiced her moves (like the ones of Linkle but emitting wind instead of electricity), a shirtless Terran is practicing with the Ball and Chain (similar attacks from Link with the Chain Ball but with Earth Element instead of Thunder Element), Aaron has his Twin Ring and practiced moves like Dazzling Gleam (similar to the fairy type move but white yellowish light instead of pink), Spirit Break (white yellowish), Lightblast (based from Moonblast), Light Cut (based from Psycho Cut) and Sparkly Swirl, Blake P with his Twin Ring practiced his new moves like Night Daze, Dark Pulse, Darkblast (based from Moonblast), Dark Cut (based from Psycho Cut) and Baddy Bad, Alban has equipped Ice Boots to surf on ice (like Marvel's Iceman), Keith is practicing with his Mini Twin Axes which did melee and combo attacks and having a bit of advantage after his last battle against Akaza, Jupiter has a Thunder Saber Gun and it is practicing with melee and combo attacks and Tetsu is practicing with his Shoulder Pads along with Double-Edged Sword and Shield.

The Digimon of the Digidestined, Tamers, DATS, Fusion Fighters and Blue Flare are practicing with their Pokémon moves, Link apart from practicing with the Master Sword, also he is practicing with the Crackling Rod, Great Fairy of Tempests, Burning Gloves with a reddish Chain Chomp included, Stormy-Eyed Epona and Hydro Spinner, Impa with the Biggoron's Sunblade and Crackling Naginata, Zelda with the Gloomy Rapier, Liquid Glorius Baton, Volcanic Dominion Rod and as Sheik practiced with the Shining Harp, Lana with Tome of the Night, Sun Faron Spear and Gate of Tides, Darunia with Darkfire Hammer, Ruto with Sun Dragon Scale, Agitha with Incandescent Parasol, Midna with the Thunderhead Shackle and in her true form with the Darklight Mirror, Fi with Liquid Goddess Blade, Young Link with Inflamed Deity's Mask, Linkle with Luminous Crossbows, green Toon Link with Lokomo Sword of Oceans and Four Sword wind variant and also the Darkfire Nice Sand Wand, the red one with the Four Sword in fire variant, blue one with Four Sword water variant and purple one with Four Sword in earth variant, Toon Zelda entered inside a Phantom armor equipping the Falming Wrecker Sword with shield included, Medli with Din's Harp of Oceans, Marin with Awakening Sunbell, Samus was practicing with Melee Counter, Melee Dash, Phantom Cloak, Flash Shift and Pulse Radar (abilities from Metroid Dread), Pit is practicing with Three Sacred Treasures, Dark Pit with the Aquarius Blade (from Kid Icarus Uprising), pink Kirby is now Morpho Knight Sword, yellow one is Buzz-Saw Cutter, blue one is Blizzard Ice, red one is Dragon Fire and green one is Space Ranger, Meta Knight, Ash is practicing with Pikachu, Dorumon Articuno, Marshadow, Latias, Lucario and Azelf, Gary is practicing with Ryudamon, Zapdos and Blastoise, Leaf with Venusaur and Moltres, Jimmy with Raikou, Marina with Suicune, Silver with Ho-Oh, Ethan with Lugia, Lyra with Celebi, May with Manaphy and Blaziken, Brendan with Latios, Dawn with Cresselia, Hilbert with Genesect, Hilda with Victini, Iris with Naganadel, N with Zekrom, Nate (trainer) with shiny Haxorus, Rosa with Meloetta, Calem with shiny Greninja, Gladion with Magearna and Silvally (evolved in a certain point), Victor with Cinderace, Gloria with Inteleon, Florian with shiny Miraidon, Juliana with shiny Koraidon (both shinies recovered his fighting skills before arriving here), Liu Kang is practicing with his nunchucks, Kung Lao with his broadsword, Kitana with her War Fans, Jade with her bojutsu, Lord Raiden with his staff, Hanzo Hasashi with the Mugai Ryu sword, Sub-Zero with the Kori Blade, Smoke with two kunais, Nightwolf with his tomahawks, Kabal with his hook swords, Stryker with his nightsticks, Cassie with kali sticks, Jacqui with his knuckle dusters, Kung Jin with his bow, Takeda with his sword and the rest with their usual weapons, also Killua was practicing being shirtless.

*Ends*

After a long sequence of training, Caleb gave the Luminous Butterflower plants to Keith Miller who then created the elixir for all the Pillars and Demon Slayers, all of them drink it and now the curse of Demon Slayer's mark won't affect them, meaning that the ones who awoke the one won't die after 25 years old.

"Okay, other weaknesses of the demons are the using Helios' head from Kratos along with Medusa's head, the Helios' head has power of the sun to disintegrate demons and the Medusa's head turn the demons into stone turning them into easy targets to destroy, also the ice attacks because the cold cauterizes the wounds and makes it more difficult for them to regenerate, the solar beam and solar blade attacks which are made of solar energy, the weapons of the Hyrule Warriors with light element too including the Master Sword, the Keyblade is also another weakness, the weapons of the Fire Emblem Warriors too and the Vampire Killers which are made of silver are another weakness because it can destroy the undead beings which include evil vampires, ghouls and demons, and lastly for the ones who don't have swords, use your strongest attacks to defeat the demons." Caleb explained and the team members nodded in agreement.

Eventually after taking a rest, Giyu is now wearing his usual haori knowing that he will see his sister after defeating Muzan, Sabito and Makomo are now wearing their Demon Slayer uniforms with their respective haoris and have their nichirin swords, Kanae is wearing back her usual haori and her two red-green butterfly hair clips, Shinobu is wearing a purplish haori still seeming like a human butterfly and Kanao is wearing back her previous pink butterfly hair clip, while the group kept training, the sword of Shinobu has added other poisonous plants in the blade, even Zenitsu was now training seriously, goodbye scaredy Zenitsu, hello to brave one, Nezuko was moved to Urokodaki's house being safe and away from Muzan and also Jigoro went there.

(Night of the Second Day)
(36 hours remain)
(Forest)
They kept training until the night arrived, just then the princesses Celestia, Luna and Cadence gave their magic to Twilight temporarily (just like they did for Twilight to fight against Tirek) this time to fight against Muzan Kibutsuji, even if she is not used to kill villains, she had to do it to protect her friends.

Meanwhile Sonic along with Shadow were running faster in the search for the Infinity Castle until they found Heartless like Shadow, Soldier, Emerald Blues, Air Pirate, Neoshadow, Hook Bat, Bulky Vendor, Rapid Thruster, Bolt Tower, Assault Rider and Nightwalker, Subspace Troops like Primids, Sword Primids, Scoop Primids, Boom Primids, Big Primids, Metal Primids, Ice Primids (light blue ones), Hydro Primids (blue ones), Electric Primids (yellow ones), Flyer Primids (Primids equipped with jetpacks), Rock Primids (Primids made of rock), Sand Primids (brown ones), Acid Primids (glowing light green ones), Vine Primids (green camo ones), Golden Primids (Primids covered of gold), Diamond Primids (Primids covered of diamond), Psy-Primids (pink ones), Light Primids (white ones), Dark Primids (Primids covered with dark matter-like armors), Fighter Primids (orange ones equipped with gloves and boots and have the ability to dodge and block), Phanto Primids (jade color ones), Ninja Primids (purple ones), Gunner Primids (equipped with arm cannons), Dagger Primids (equipped with daggers), Claw Primids (equipped with wolverine-like claws), Archer Primids (equipped with bows and quivers of arrows), Bomber Primids (equipped with bombs), Medic Primids (equipped with head mirrors with purple bands), Drill Primids (equipped with drill helmets), Hammer Primids (equipped with hammers), Sword and Shield Primids (equipped with swords and shields), Ball and Chain Primids (equipped with Balls attached to chains), Laser Primids (equipped with laser guns), Parasol Primids (equipped with Parasols), Spear Primids (equipped with spears), Staff Primids (equipped with staffs), Reaper Primids (equipped with scythes), Whip Primids (equipped with whips) and Yo-Yo Primids (equipped with twin yo-yos), and Corrupts Digimon like DarkLizardmon, DarkMaildramon, DarkSuperStarmon, DarkTyranomon, Arcadiamon (rookie, champion and ultimate/perfect), Argomon (rookie, champion and ultimate/perfect), Deltamon, DexDorugamon, DexDoruGreymon, Dobermon, Dokugumon, Dracmon, Dragomon, Bakemon, Entmon, Eyesmon Scatter Mode, FlameWizardmon, Flybeemon, Flymon, Ogremon, Fugamon, Hyogamon, Rebellimon, Greymon and MetalGreymon (blue), BlackGarurumon, ShadowWereGarurumon, BlackGrowlmon, BlackWarGrowlmon, BlackGargomon, BlackRapidmon, Gesomon, Ginkakumon, Gizamon, Goblimon, Golemon, Chamelemon, Chrysalimon, Green Coredramon, Groundramon, Cyclonemon, GranDracmon, Gyuukimon, Kuwagamon, Okuwamon, Hookmon, Infermon, Musyamon, Orochimon, Keramon, Oleamon, Kyukimon, Lavorvomon, Orochimon, Loudmon, Parasimon, Raremon, RedVegiemon, Runnermon, Saberdramon, Sangloupmon, Vilemon, Tuskmon, Veedramon (virus), Vulturemon, Soundbirdmon, Salamandermon, Sunarizamon, Waspmon, Weedmon, Wendigomon, Woodmon, Yanmamon, Xiangtianmon and Zanmetsumon.

"Look." Sonic said before he and Shadow dashed towards the enemies.

Both hedgehogs continued until they found the Infinity Castle and jumped trying to enter but suddenly the Infinity Castle disappeared as Sonic and Shadow landed in the ground.

"It disappeared." Shadow said.

"Let's try to find it in another place." Sonic said before dashing again.

Both of them dashed everywhere as they managed to find the Infinity Castle but then again disappeared every time that they managed to find it.

(Ubuyashiki Mansion)
Both hedgehogs returned to the mansion and explained that the Infinity Castle disappeared everytime they managed to find it.

"We searched the castle everywhere but every time we try to land, the castle disappears." Shadow explained.

"Enter the Infinity Castle like that is not gonna be easy, the only way to enter there." Aries said before whispering to both hedgehogs.

"What…? It seems very suicide…" Sonic whispered with concern.

"I know but it's the only way I know, however Capricorn will cast a spell which will prevent Nakime to separate us and also Shinobu along with Tamayo and Yushiro are preparing the Anti-Kibutsuji Drug that will age Muzan Kibutsuji over 50 years in a single minute." Aries explained.

(Butterfly Mansion)
Later in the Butterfly Mansion, while the team members are sleeping for the next day, the Zodiac Warriors and Elemental 10 are speaking with Tamayo.

"Even if I die after injecting the Anti-Kibutsuji drug into Muzan, please I want to be reunited with my family in the afterlife, I will only be able to rest in peace until Muzan has been defeated." Tamayo requested the Zodiac Warriors and Elemental 10.

"I see you want to reunite with your family so much." Cancer said and she along with the others nodded sadly in understanding.

(Dream)
Tanjiro was having a weird dream, one where he is with Yoriichi Tsugikuni.

"My apologies, young one; I didn't mean to cause you grief, but I did want to apologize to you before I say anything else. All my life, I had been blessed with great powers, abilities that separated me from nearly everyone else. I was born with this Demon Slayer Mark, able to see things that no one else could. However, it was not until I met that man that I truly understood why I had been born with these abilities. Muzan Kibutsuji, the Progenitor of the entire Demon Race, I knew as soon as I saw him, that I had been born to kill him. Yet, even in that, I failed. I came so close to ending him then and there, but he still managed to slip away and reform his body. Perhaps that was sin enough, but I managed to drag your family into Muzan's grudge against me. The Hanafuda earrings you wear now were made for me by my own mother, as she had believed I was deaf and wished for the gods to perhaps open my ears. After I met Sumiyoshi and his family, I decided to leave my earrings with him, as a way to thank him for everything he had done for me and a way to apologize for the trouble I had brought. I had no idea that Sumiyoshi had memorized my Sun Breathing forms as I demonstrated them for his wife, passing it down through his family as a kagura dance to honor the god of fire. Even after all these years, however, Muzan still fears even the memory of me, including the only Breathing Technique that can truly hurt him. I do not know exactly how, but he must have heard of the Kamado family's Hinokami Kagura, fearing any relation to my Sun Breathing, he decided to wipe it out for good. If I had not been so foolish, your family would not have been killed that night." Yoriichi explained with sorrow and remorse.

Now hearing the whole backstory, he felt his heart wrenching with pain and understanding that his family was tormented by Muzan across the years, clearly the King of the Demons is the King of the Cowards who wants to avoid death at any cost and felt his eyes well up with tears but he stubbornly held them back as he got to his feet.

"Please...don't apologize, Mr. Yoriichi!" Tanjiro begged tearfully, trying to be as strong as possible. "None of this was your fault, and I know Sumiyoshi would say the same thing! Even if my family was revived, Muzan is to blame for being a torment and haunting for my family; his actions are his own, no one forced him to do any of the horrible things he's done over the years. Not only that, but, if you hadn't saved Sumiyoshi that day, my family and I probably never would've existed in the first place."

Now with those he felt ready to stop Muzan and end his reign of terror in Japan.

"Thank you, Mr. Yoriichi!" He said before wiping his tears away.

"Now I have one more thing to tell you, the sword you wield now it's my sword, my spirit will be there and I will come out for the battle, my spirit won't rest until Muzan Kibutsuji is killed." Yoriichi explained before adding. "Even after Muzan is dead, I have one request for you: keep the Dance of the Fire God alive, the Sun Breathing, and pass it on to future generations."

"I promise!" Tanjiro said and Yoriichi nodded before disappearing into light particles.