The skies were red. Smoke filled the air. A lake of lava surrounded the castle in the center of the body. Two pairs of brown shoes clapped against the volcanic rock, pacing towards the mountain. These were two men who were darting towards the castle. These men had very round noses, and mustaches that patterned small circles. They had matched the same brown hair and same blue eyes. These were men of Italian descent. These men were brothers.

Leading the way, was the older brother, though only by minutes. He was shorter, and he rocked a red long-sleeved shirt, with blue overalls over it. These overalls strapped over his shoulders with singular golden buttons on his pectorals. He had worn white gloves and a red hat over his head. On the front of the hat was a white circle, which encased a red 'M'. The younger brother trailed behind, a similar outfit. Though instead of red, he rocked the color green. He had an 'L' on his hat in the white circle.

"Come on, Luigi! Times-a-wastin', and the princess needs our saving!", the younger brother encouraged, picking up his pace as he panted.

"Do we have any power plants, Mario!?", the younger brother, Luigi questioned. Power plants were a form of power-ups for them to utilize. They helped with efficiency in battle.

"One ice flower! You want it!?", Mario offered to Luigi, knowing they might need it. He pulled it out, ready to hand it to him as they ran.

"Uh-", he started, before they ran into creatures. Before them were small brown creatures, with big round eyes, and a big frown. They had tiny feet to get them around. These were called goombas. Behind the goombas were turtles who stood on their back two legs. They had large round snouts, along with round eyes. Their shells varied in color. Green-shelled turtles were on the ground. Red-shelled turtles had white wings extending from their shells, and could fly. These turtles were known as koopas.

Mario threw the blue ice flower to Luigi, who panicked. "M-Mario! You're the hero here! Wouldn't you be-a better at using this!?", he questioned.

Mario shot Luigi a look of disapproval. "Just use it!", he demanded, causing Luigi to jump a bit. He obeyed, and his green shirt and hat had become a baby blue. His overalls turned into a vibrant green.

Mario and Luigi charged towards the creatures, ready for combat. Luigi extended his arms out, balls of ice coming out of his gloved hands. His eyes had been fierce now. The ice balls slammed into goombas, encasing them in ice. The younger brother slid them all into the opposite direction.

Meanwhile, the shorter brother was hardly the koopas. He slammed his foot onto one's head, and it retracted into the shell. Mario grabbed the shell, and tossed it at the airborne koopas! Two koopas well on their backs, before retracting into their shells. By the time Mario had finished up, Luigi had finished up his batch of underlings.

The shorter brother approached the taller one, crossing his arms and offering a look of disapproval.

A look of guilt decorated Luigi's face, before he sighed. "I'm sorry, Mario."

"You shouldn't be putting yourself-a down like that!", Mario began to scold. "How many-a times do I need-a to tell you, Luigi? You're amazing! You aren't below me in anyway!", the red-hatted hero assured.

Luigi couldn't help but smile. He nodded at Mario, and they both looked across the bridge. On the other side of the bridge laid the large, red gates to the castle that stood before them. As one might assume, Mario and Luigi were the heroes of this world. They were once simple plumbers in New York City, but now, they were the saviors of the Mushroom World! They had saved the famous Princess Peach from Bowser, the Koopa King, on countless occasions! It got so consistent that Mario and Peach even ended up close to the point that there would be subtle flirting at times. They had become so acquainted that Luigi even met a princess himself, one by the name of Daisy. They had made a lot of friends outside of the two princesses, too! Now, it was practically routine to stop Bowser and whatever plan who would muster up. This time, he was recycling an old plan. He would force the Princess' hand in marriage so he could rule the world! But like always, Mario and Luigi were here to stop it.

"You-a ready, Luigi?", the shorter plumber asked.

"You know it, Mario!", Luigi replied. They both charged through the doors, to be met with tons of creatures. These were Bowser's underlings, the Koopa army!

Without hesitation, Mario grabbed his brother's hand, and spun him around. Luigi screamed in a panic at first, before realizing what Mario was doing. He smiled, and extended his arms out, throwing constant balls of ice. As Mario spun his brother, he carefully treaded forward, careful to avoid anything that might be tossed their way. Especially certain hammers from a certain type of soldiers.

It wasn't long before they were done with the enemies in the room, and they were huffing a bit, as they were very dizzy from the move they just performed.

"C'mon, Luigi. Let's-a follow this red carpet!", Mario instructed, before running off, with an imbalance. Luigi followed suite.

They battled through different rooms, halls, floors, and stairs, before finding themselves before a door that was crimson red, with hints of gold lacing the outside of it. The brothers barged into a throne room. At the end of it had been a large, red, chair. There was a red carpet leading to it. The ceiling hung high. Dimly lit candles were evenly spread out through the room. Bricks filled the floors, and the walls. Above the throne, was a large window that showed off the red sky. Curtains were open, and hanging above the throne, in a cage, was the leader of the Mushroom Kingdom, Princess Peach!

She had worn a pink dress with a blue ruby on the chest. She had white sleeves that extended out to be gloves. She wore blue, round earrings and flaunted a crown atop of her silky blonde hair. Her lips were small, plump and pink. She had eyes that were a baby blue. When she noticed them, she gripped the bars of the cage. "Mario! Luigi! It's a trap!", she warned.

"Wha-?", Mario began to question, only to be slammed into a wall by a giant, meaty hand. It was yellow, and had claws along each of it's four fingers. Mario looked to see Bowser.

Bowser had red eyes, and orange skin, with the exception of everything above his large snout being green. He had large eyebrows that were a mix of orange and red, as if they were fire. He had a mohawk of the same color. Sticking out on either side of his head, were horns. He wore sharp-studded, metal cuffs around his arms, wrists, and neck. He had a large spiked turtle shell on his back, with two more spikes sticking out of his orange tail.

"Hello, Mario!", the Koopa King greeted with his deep, nasty voice. Mario struggled to escape, causing his nemesis to only laugh. Mario had been stuck.

From behind, Luigi jumped over Bowser, and stomped his feet into the King's head with a loud yell. The Koopa growled in pain, loosening his grip on Mario. "Mario! Get Peach! I will distract-a Bowser!", Luigi instructed.

Mario took Luigi's advice. He was worried for his little brother, but he had to have faith. He had to believe in Luigi. As soon as he dropped to the ground, he landed on one knee and darted for the throne. He leapt on and off of it, clinging to Peach's cage. "Hang on, Princess! I've-a got you!", the plumber assured. Peach only brought her hands to her chest in worry for the brothers. She knew they were capable, but she hated seeing them in harm's way, let alone because of her!

"You think you're tough, little guy?", Bowser threatened. "Let me show you tough!", he began to open his mouth, and Luigi took this opportunity and chucked an ice ball right into his mouth. Luckily for Bowser, his teeth caught it, and crushed it. He only looked even more infuriated now. He charged at Luigi, throwing a barrage of punched.

Luigi panicked, and danced around these punches, as he threw ice balls at Bowser. Mario, in the meantime, had finally broke Peach's cage open. "Jump on-a count of three!", he ordered. Luigi barely jumped over a punch of Bowser's. He pressed his right foot to his arm, and leapt towards Bowser, kneeing him the face. Bowser growled, and slammed Luigi to the ground. His clothes faded back to the original green hat and blue overalls.

"One!"

He rolled out of the way of Bowser, and ran towards a pillar. Bowser was following shortly behind. Luigi leapt to it, and bounced himself off using his feet. He stomped himself into Bowser's head, as he'd done before, and rebounded himself. He had been heavily panting at this point.

"Two!"

Bowser swung his tail around, knocking Luigi off of his feet, and he fell on his back. He ran to the plumber, and kicked him across the room, into the throne. He made his way to him again, and lifted his foot to stomp on the green plumber.

"Three!", Mario finished, before the two jumped down. Mario stomped into Bowser's face, causing him to stumble back. Peach landed safely behind him, and helped Luigi up. As Bowser regained his posture, Mario got into a defensive position in front of Luigi and Peach.

But to their surprise, Bowser didn't attack them. Instead, he walked to one of the pillars, and slammed his fist into it. Bricks fell off from all around it, revealing a red cylindrical machine. It had a clear glass patch, with one star in it. It had two eyes, and was green. It's edges were sharper than the power stars that made it's user temporarily indestructible. "What's-", he started, only to be cut off.

"The seven Star Children are the only ones who can wield the seven Mega Stars!", Bowser began. "In here is one of those seven Mega Stars!", he pointed to the green Mega Star. He attached his large hand to a lever on the inside of the device. "This will send the Star's power to the bottom of the castle, and my underlings will use it to build a tracker for me!"

"You're plan won't-a work!", Mario shouted confidently. Bowser only chuckled, and pulled the lever. The tube lit up, with a green light, and the energy began pumping to the bottom of the castle.

"That's the thing, Mario! I'm a Star Child!", Bowser warned. Mario only gulped, and he started approaching them. At the same time, a purple portal opened, and a red echidna landed right on the ground, in front of Bowser. He jumped back a bit, and started questioning himself. "Did it malfunction..?"

The echidna groaned and rubbed his head. He stood up and looked around. He saw three people cornered with a big dinosaur turtle thing on his other side. He immediately looked to the turtle, and started speaking. "Listen, big man. You better leave these guys alone, or you're gonna have to deal with me!", he warned.

Mario looked to Luigi and Peach with a look of confusion, who both only returned the same looks.

"Do you have any idea who I am!?", Bowser shouted, offering a fierce posture.

Knuckles only started walking towards the tyrant. "No. And to be frank, I don't care to, either!", he spat back. "I'll admit that I'm not the brightest. But it doesn't take a genius to figure out you're just some ugly turtle dragon who can't get off of his high horse!", the echidna insulted. Luigi's jaw dropped at his bluntness.

"You skinny little rat! I'll crush you!", Bowser threatened.

The echidna's purple eyes locked with the Koopa King's fiery red eyes. "Don't underestimate me.", he warned, bluntly.

Bowser charged at the echidna, who jumped into the air, before throwing a fierce punch. Bowser was sent flying back, and hit a pillar. The echidna charged towards Bowser, and threw a few more punches, before being met with the pleasant surprise of flames from his mouth.

The echidna was caught off guard, and jumped out of the way of this. Unfortunately, it left him open for Bowser to slam him to the ground. The Koopa King did exactly that. As soon as he lifted his hand, the echidna kicked into the Koopa King's stomach, before throwing a full strength punch. Bowser was knocked to the ground, and the echidna stood over him.

The Koopa King used his tail to swipe the new mysterious hero off of his feet. He slammed his palm to the ground, and launched himself to the wall. He dug his sharp knuckles into it, and stuck. Bower stared in disbelief, before shouting. "Who are you!?"

"My name is Knuckles.", he started, before the sound of glass shattering caught their attention. They both looked to see that Luigi smashed the machine open with his hammer, and Mario was grabbing the Mega Star.

Bowser went to charge towards the two, but Knuckles caught him off guard with a punch. "Pay attention. I was talking.", he warned.

"You twerp!", Bowser hissed, as he went to grab Knuckles. The emerald guardian jumped back, and watched as Mario, Luigi, and Peach ran off with the star.

"I'm assuming that those are the good guys, so I'm going to get going. Maybe you won't underestimate this little rat next time we meet.", Knuckles quipped, before turning around, and running off to catch up with Mario and the others.

Bowser didn't bother pursuing them. He knew when it was best to fall back. They had taken the Mega Star, and he was infuriated. But that rage faded when he realized they still preserved some energy from the Mega Star. He could use the energy to track Mario wherever he was, so long as he had the Mega Star. He had the element of surprise, now.

Meanwhile, just outside of the castle, Mario and Luigi were observing the Mega Star as they walked, Peach following close behind. "What is a Mega Star?", Luigi asked Mario.

"I have-a no idea!", Mario responded, examining it closely. He handed it to Peach, who looked for herself.

"Bowser said there is seven of them. Maybe Toadsworth will know something about it?", she suggested to the brothers. "Nonetheless, it must be powerful if Bowser is trying to use them."

"Sounds similar to what we've got on my world.", Knuckles chimed in, finally having caught up with the group.

Mario, Luigi, and Peach stopped. Neither Mario or Luigi knew what to say. This guy popped out of a portal and fought off Bowser alone! Mario had done that himself, so he knew how impressive a feat it had to have been.

"Thank you for helping us, earlier!", Peach spoke up, being sure to put manners above everything else. "If you don't mind me asking, what do you mean by your world?", the princess questioned.

"I'm not from here. I lost something valuable and it ended up here, on your world.", he explained. "I think.", he corrected. "I hope.", he finished.

"Oh! Well maybe you could stick with us and we could help you!", Peach offered.

"I appreciate that, but it seems you have your hands full enough with this Mega Star stuff. I think I'll be off on my own.", Knuckles explained.

"Wait!", Luigi cut in. "You said that the Mega Star sounds similar to what you-a have on-a your world! Maybe you coul-ad help us by explaining what your world has, and we can-a help you by tracking what you lost!"

Knuckles crossed his arms, and closed his eyes, tapping his foot to the ground. Restoring the Master Emerald was his top priority, and if he had help, things might go a lot faster. After a moment of thought, he opened up his eyes. "Alright. I accept."

"Great!", Luigi smiled, nervously. "Nice to meet you, Knuckles!", the plumber complimented.

"I'm sure it would be nice to meet you if my situation wasn't so serious.", Knuckles responded, earning a confused look from Luigi. Knuckles stuttered a bit, before correcting himself. "I-it's nice to meet you, too.", he said. He didn't give it a second before speaking up once more. "So what should I call you guys?", Knuckles asked.

"I'm-a Mario!", the red plumber greeted, finally speaking up.

"I'm Luigi!", the taller brother followed.

"And I'm Princess Peach!", Peach chimed in.

"A princess, huh? So you must rule your own land or something, right?", Knuckles questioned.

"Or something.", the princess of the Mushroom Kingdom answered.

"Great. How do we get there?", the echidna followed up.

"We'll go on the Odyssey!", Mario answered.

"The what-now?", asked Knuckles.

"It's an airship I have!", Mario happily answered. "Let's get-a going to the Mushroom Kingdom! Follow me and Luigi to the Odyssey!", he instructed, happily leading the way. Peach and Luigi immediately began following Mario. Knuckles was going to questioned why this Mario guy just owned an airship, but remembered that Tails had his own plane. He shrugged it off, and placed his hands behind his head, before following after the group. Hopefully this Mushroom Kingdom was prettier looking than this place!

Meanwhile on Mobius...

Sonic and Tails had just pulled the plane up onto the street he lives on, before carefully parking it into his garage. Sonic hopped off of the wing as Tails got out of the pilot's seat with the Chaos Emerald he had. "I'm telling you, buddy! I don't know how your neighbors can put up with that!", Sonic reminded.

"Okay, okay! I get it, Sonic! I have to do some tune-ups on the Tornado tomorrow, and then I'll relocate!", Tails finally gave in.

"Wait, the Tornado seemed fine when we tested it!", Sonic pointed out. "What else needs tuning?"

"It was fine when we tested it.", Tails started. "But on the way back, the Tornado kept switching to it's manual power, rather than using the Chaos Emerald. That should only happen when there's no Emerald powering the Tornado!", he explained as he opened a door in the garage for Sonic. It led into Tails' kitchen.

"Weird.", Sonic started, before walking through the small kitchen. It had orange cabinets, brown counters, and a white island with an apricot topping. There was a white refrigerator with a stove to it's left, a toaster and microwave to it's right. The floor had checkered black and white tiles which transitioned into a small living room, with a sofa-bed across from a small television. There was a blanket and pillow on said sofa-bed. Sonic flipped the television on and sat down. The television had opened to the news, and it was covering that Angel Island has fallen once again. Sonic furrowed his brows, and cleared his throat. "Yo, Tails! What if it wasn't the Tornado that malfunctioned, but it was the Chaos Emerald?", the hedgehog suggested to the kistune who was approaching from the kitchen.

"I'm not sure how-", Tails stopped himself when he saw the television screen. He looked to Sonic, with a look of determination. "Let's go."

It only took a little bit for Sonic and Tails to find themselves at the Master Emerald altar on Angel Island. It was no longer in the sky, but rather, in the ocean. They had seen it was empty and Knuckles was nowhere to be seen. Sonic leaned down to grab a small shard of the Master Emerald. "That's not good.", he spoke, as he put the Master Emerald shard away. He decided it was best to hold onto it for now.

"Yeah, the Master Emerald shattered again.", Tails commented.

"It's also not like Knuckles to just leave a piece of it behind when that happens, either.", the hedgehog pointed out.

"Oh, that's- oh no!", Tails panicked, now worried for the Echidna's safety.

"Don't worry, buddy.", Sonic said, as he and Tails looked around some more. "We'll find Knuckles.", he continued. Tails stepped on a claw, with a torn wire attached to it. He picked it up, beginning to examine it. He started to dust it off as Sonic continued. "Besides, he can take care of himself, wherever he is!", the mobian hero assured.

"Uh.. Sonic?", Tails called out. Sonic sped over to Tails, who held out the claw to him. "You might want to see this.", he advised. The blue blur took the claw and started to examine it himself. That's when he noticed a faint Eggman logo. He handed it back to Tails. "What do you think we should do, Sonic?"

Sonic pondered that question in his head for a moment, though the answer was obvious. He pulled out the red Chaos Emerald he'd collected earlier that day, ready to find out what was going on. He flashed a cock grin, and shot Tails a thumbs up.

"It's time to pay Doctor Eggman a visit!"

A/N

Okay, guys! That's the first two chapters done, and now both Mario and Sonic have started a new adventure! Will Knuckles be able to find the shards of the Master Emerald? Are they even on Mario's world? Will Sonic and Tails be able to figure out what's wrong with the Chaos Emeralds? Or where Knuckles is? How is Bowser planning to use the Mega Stars? And will Mario and gang try tracking any down? If so, how will they do it? Stay tuned to find out next time on

Mario & Sonic: Between Worlds!