On Final Destination, Master Hand turned Master Core.

Mario: "So, that's his true form?"

Ness: "No, somethings different. My psychic powers won't work. I can't concentrate with this swarm of darkness."

Toon Link: "Ugh, I can't see anything."

Falco: "Thank you, Sherlock."

Spider-Man: "This is gonna be tough. So don't fight each other."

Soon, the darkness cleared up and showed Master Core in the background in his Master Core form, a large humanoid creature.

Master Core: "I am Master Core! You shall now bow down to me as the ruler."

Shulk: "Ugh, I'm sick of all those god-like entities thinking they can dictate the world into their own image."

Goku: "Even I faced a god, doesn't mean they can't do that."

Master Core: "Hmm? My own image? What are you babbling over there about, my little foes? My goal is to simply eradicate humanity and wipe out all of existence."

Naruto: "Eradicate humanity?"

Twilight: "Wipe out all of existence?"

Cloud: "Reminds me of that bastard, Sephiroh."

Spider-Man: "Or, from my world, Painset Shimmercakes."

Mega Man: "Like we'll ever let you take control of this world."

Master Core: "I admire all of your insolence, but that alone won't be enough to beat me."

Sonic: "Don't worry, you guys, we'll get rid of this guy no problem. He's probably a lowlife loser who thinks he belongs in this world by taking control over it."

Master Core: "I can see that arrogance is upon you all as well."

Rainbow Dash: "Don't talk to my blue blur like that!You are so going down."

Master Core: "Very well. Brace yourselves for this upcoming nightmare."

Spider-Man: "I have better nightmares."

Master Core, in his Master Giant form, Spawned two additional arms with glowing hands. The arms swept the stage, then merge back into its chest. Everyone avoided the grab. He then quickly swiped his arms across.

Lucas: "That was cl—"

A spilt second later, they were all launched.

Diddy Kong: "You were saying..."

Master Core then produced six electrified orbs surrounding the fighters.

Ryu: "Trapped."

Master Core then lifted up the stage and all fighters were shocked. He then opened up a vacuum effect within his head. Everyone tried to run away. Fast Fighters like, Sonic, Rainbow Dash, Captain Falcon, Little Mac, Zero Suit Samus, and Fox were pulling the slow fighters like Fluttershy, Jigglypuff, Ganondorf, Robin, Mr. Game & Watch, and Samus away. They were all successful. Master Core then tried to headbutt the fighters, but a small portion of them were caught but were buried out quickly. He then pinpointed miniature bombs across the stage, but everyone simply crouched or airdodged.

Blaze: "Now, it's our turn!"

Everyone was attacking Master Core left and right and he helplessly took those consecutive hits. When they stopped, Master Giant was fed up.

Master Core: "Now you're really pushing it. Why don't you try this!"

Master Core screamed and created a massive shockwave (similar to Tabuu's Off Waves) and launched all the newcomers from Smash 4. They all fell into the abyss.

Everyone: "NOOOOO!!"

Mane Six: "Sunset Shimmer!!"

Spider-Man: "Akame!!"

Blaze: "Lucy!!"

Master Core: "Even you two are finished!"

Master Core then same attack to Spider-Man and Zander Blaze and the two OC Heroes have fell into the abyss as well.

With that, Ike and Charizard attacked Master Giant with their Eruption and Flare Blitz, defeating him. Master Giant then reverted onto the stage into his Master Beast form. Master Beast emanated lightning to himself, similar to Pikachu's Thunder, and the all fighters dodged. Those who projectiles were spamming them. Soon after, Master Beast targeted one group of fighters in front of him and spawned spikes from underground and attacked them. While those fighters were on the verge of going over the upper blast line, the other fighters were on the opposite side of Master Beast attacked him with Smash Attacks.

Peach: "I hope the others are okay."

Link: "At this rate, I can feel we can actually beat him."

The airborne fighters were still alive but landed back on the stage attacking Master Beast with their aerials.

Marth: "There's no way we can lose."

Master Beast then leaped off stage.

Falco: "Where the hell di—"

Everyone: "Wahhhh!!!"

He crash-landed back onto the stage, slightly tilting it a bit.

Ike: "Keep your ground, everyone!"

Rarity: "It's easy for you to darling."

Kirby: "You have a lot of heavy armor, and I'm as light as a balloon."

Meta Knight: "We Star Warriors should still be able to have as much stamina as we possibly can."

Lucario: "I can feel his aura. We are in great danger."

Master Beast's aura was visually screaming. He then performed a last-ditch attempt by jumping into the background and diving back down with a huge bite. Some fighters jumped over the attacked, but others fell victim and were instantly KO'd. The Brawl Newcomers' deaths weren't in vain. Roy, secretly charging up his Flare Blaze, blasted Master Core our of his beast form. Master Core then reverted to Master Edges.

Ganondorf: "Tch. Pitiful."

Master Edges briefly followed the fighters, but they somewhat dodged the flurry of slashes with their shields.

Captain Falcon: "Swords? I guess he's taking a different approach."

The final slash of the move was barely dodged, so the hitboxes were very effective.

Mario: "He has swords, so we have to increase our defense. Link, Marth, Roy, you three will carry out as our offense."

Sheik: "You have all very powerful weapons, so we need to defeat this guy by any means necessary."

Master Edges launched four spinning projectiles (two at a time), but Ness and Mr. Game & Watch absorbed them. Then, the three remaining swordsmen were attacking Master Edges with their Smash Attacks, Aerials, and Special Moves.

Roy: "Crap. If only we had the rest of swordsmen here. We'd be an unstoppable force with Ragnell, The Monado, the Yato Blade, or the Buster Sword At our side."

Marth: "We have to do what we can do here. A true swordsmen would fight to the end."

Link: "Don't push yourselves, guys. Keep a cool head."

In the midst of battle, Master Edges knocked the three of them offstage by simultaneously slashing them with all five swords. Link recovered back onstage with his Clawshot while holding onto Marth's hand, who was holding onto Roy's hand. The three returned back onstage, bracing themselves. Master Edges emitted two large projectiles at the same time. The capacity of the projectiles couldn't be absorbed, so Ness and Falco reflected them. While doing so, Fox, Samus, and Falco were shooting at Master Edges.

Luigi: "That should do the trick."

As a last-ditch attempt, the five swords surrounded the fighters across the stage. The first four swords were starting a combo with minor hits on each side. Half of them were trapped. The finale hit made the giant sword on top slash within the middle of the stage, giving it a satisfying deadly blow. The Melee Newcomers were launched and soon met up with their doom.

Luigi: "Oh, man! Now there's 12 of us here. What're we gonna do?"

Mario: "I've realized something. Whenever he reverts to a new form, he gets smaller, but also a little stronger. His next form might be around in our playground."

Just then, Donkey Kong Giant Punched Master Core and he reverted into Master Shadow.

Kirby: "They're us. But they're slightly larger."

Fox: "Clones!"

Ness: "The only way to defeat them is to know our own moves, strengths, and weaknesses."

Mario: "Sounds like a plan!"

The Original 12 Fighters then fought their clones. It was actually very easy and it took no more than 5 minutes. Mario defeated his by using the F.L.U.U.D. trick, Donkey Kong defeated his by using Forward Aerial, Link beat his by using his Bombs, Samus beat hers by using her Charge Shot, Yoshi uses his Egg Lay to beat his clone, Kirby used a Rejected Inhale followed by Final Cutter, Fox spamming Aerials, Pikachu uses Thunder, Luigi with Super Jump Punch (close), Captain Falcon with a midair Falcon Dive followed by a midair double-reverse Falcon Punch, Ness with PK Fire followed by PK Thunder, and Jigglypuff with Devastating Rest.

Master Shadow was defeated and in the middle of reverting, he say.

Master Core: "I'm surprised that a few of you all made it this far. But I wager none of you could survive this next form."

Soon everything went pitch black and when things clear enough, there was massive fortress right next to Final Destination.

Master Core: "This is... MASTER FORTRESS!!! Come and find me, if you dare."

He summoned Maxim Tomatoes, Fairy Bottles, Heart Containers, and Food. The fighters ate them and devised a plan to find Master Core.

Ness: "I've pinpointed Master Core. He is in a center of this fortress being held up by his core. We need to get to that core. But inside, they are enemies and danger zones that we need to avoid."

They all went inside and their first target was a small core.

Lethiniums were shooting, Plasma Wisps were blasting, Stalfoses were attacking, and Gemmers were poking. The enemies were now pitch-dark, shadowy forms and our heroes were being ambushed by them, but DK was able to get through them and hit the core with a fully-charged Giant Punch.

Luigi: "A new path is opened."

They all went back a bit and forged on the new path. They went up enemy slopes and fell into a pit where there were 5 platforms and below it was a large pool of yellow, molten lava and the Core was right above. There are a lot of enemies, but Ness was able to PK Flash to the core.

Mario: "We did it! We—"

Then, everything fades away.

Master Core: "I theorized that decoy would fool them. Now, time to recreate reality into my own image."

Master Core locked all 73 fighters, in trophy forms, in a room and pursued his quest for world domination. A while later, the whole world was up in flames. The balance between destruction and regeneration were unorthodox.

Master Core: "Yes, Yes, YES!! No one can stop me now! You heroes have failed to save your worlds!"

In a dark room, Mario's trophy gave off a bright, blinding light. He got revived by the Dedede Brooch.

Mario: "Ugh... what happened?"

He then remembered Ness destroying the core, then the explosion and everything after that was blank.

Mario: "That core must've been a decoy. He really fooled us. But, how did I get revived?"

Then, Mario saw a lump coming from his overall pocket. There, he found a Dedede Brooch.

Mario: "Heh. Thank you, King Dedede. I guess Kirby has misjudged you."

Mario then looked at his allies and felt anger.

Mario: "I'll be back for all of you. Dang, this door is locked."

Mario turned around and went through the portrait of a Final Destination. When he got there, Master Core (still in his Master Fortress form) immediately spotted him.

Master Core: "What?! How are you still alive and escaped?! No matter, you're already too late, plumber boy."

Mario: "I'll defeat you and bring this world back to normal."

Master Core: "Tch, tch, tch. Why do you even bother trying? You cannot win."

Mario: "Then tell me why?"

Master Core: "Tell you what?"

Mario: "Why you're doing this? Why do you have so resentment towards this world?"

Master Core: "Well, I have personal vendetta against you and those other heroes. And before you asked me, what am i? Do you know Tabuu?"

Mario: "We stopped him a long time ago in Subspace." (gasps) "What is your relation of him?"

Master Core: "He is my "father"."

Mario: "What!?"

Master Core: "After you and those heroes defeated him, I was created by him to take over this world if he were to ever fail. My only purpose is to pick up to where he left off."

Mario: "Not if I can help it."

Master Core: "Then come and find me, Mario!"

Laser-focus on his target, Mario went inside Master Fortress destroying enemies one-by-one without any hesitation. He found a semi-core which he destroyed and a new path is opened.

Mario fell into a pit. There, the yellow molten lava was at a higher level, a six platforms. He passed through them and entered the hallway where he easily defeated enemies one-by-one. He entered another room where there was a small pool of lava and Mario went through more enemies in it. He entered a giant room where there was two moving platform ascending upwards and above, there was the core.

Mario: "There you are."

As Mario got closer to the core, the heart kept beating rapidly. But, one Stalfo knocked Mario off and then faced off.

Master Core: "You never learn do you. You cannot win this."

Mario grabs the Stalfo and threw it into the danger zone and made his way back to the platform.

Mario then came face-to-face with the core.

Master Core: "Don't you dare touch my core!!"

Mario kept hitting the core until it exploded.

Master Core: (While being blasted away) "NOOO! YOU IMPUDENT MORTAL!"

Everything went blank for a moment, then Mario was back at Final Destination saw Master Core's true form. A glass, spherical object. He was silent, defenseless, and completely helpless.

Mario: "So, this is your true form, huh?"

Mario kept beating it and until its final hit: a fully-charged Side Smash. He successfully KO'd Master Core.

Mario: "How disappointing."

After that, he went back to revive his fallen allies, Link was the first one.

Link: "Ugh... uh, Mario?"

Mario: "It's finally over."

Link: "Good."

Link got on his feet and revived Kirby.

Kirby: "You two are alive, I'm guessing that core monster is defeated."

Link: "Correct."

Kirby gets up too and revived Pikachu.

Pikachu: "Pika...?"

Sooner or later, everyone was revived and Mario explained what happened with Master Core's demise.

Cloud: "I take it that we're done here, am I correct?"

Mario: "There's still one more thing we have to do."

Goku gathers all the seven Dragon Balls and Shenron has been summoned.

Shenron: "You who has collected all the 7 Dragon Balls, what is you wish?"

Goku: "Internal Shenron! I wish for you to return the world the way it was before Master Core took over."

Shenron: "Your wish is granted."

With that, everything returned back to normal with a help of Shenron. Everyone landed back into their own homelands in peace. At least for now.

(A/N: End Credits, next page.)