Galactic Federation space station, near planet SR388

Metroid dimension

As the blue tunnel of the interdimensional rift sped by Samus' Gunship, the strike team inside began to review their plan. Mario brought up a hologram of the station and noticed a red point near the station's core. He pointed to it with a smile, with Fox and Sheik beside him. "So the piece is near the station's core?" Sonic asked. "How are even gonna get access to it?"

"The Galactic Federation knows me well." Zero Suit Samus reported from the pilot's seat. "I just need to get permission to land at the station and, possibly, get access to the core." Mega Man stepped forward. "That's good. I guess they'll probably help us extract it, too?" He was just glad Wario wasn't here. He would constantly annoy him about how cool his Mega Buster was.

"We'll have to see, robot." Samus answered before noticing the bright light ahead. "Looks like we're reaching the light at the end of the tunnel." She gripped the controls as everyone else braced themselves. "Prepare for entry in 3…2…1…"

Samus' Gunship flew out of the open portal just before it shut and rocketed toward the space station. Samus flipped one of the switches that opened the comm system. "This is Samus Aran, requesting a landing pad. Clearance code one-nine-eight-six." For a few moments, there was no response. Only static. "I say again, this is…"

A voice then came through the comms. "(static)Samus…(static)don't…(static)are overrun…(static)out of here…(static)no, no…" A laser blast soon followed, ending the transmission. "That can't be good." Fox whispered. "Looks like we need a new plan." Sonic added as Samus brought the ship to a stop just out of range of the station's guns and stood up from the pilot's seat.

Fox turned to the rest of the team. "Alright, listen up. If this station is under Subspace control, their defenses won't be easily breached. We'll need a diversion." Sonic sighed. "So much for the 'get in, get the Stone piece and get out' plan." Fox smirked. "If only it were that simple, speedy."

Samus noticed Sheik off in a corner of the ship. "Somewhere to be, princess?" the disguised Zelda nodded as Samus armed herself with her Paralyzer. "McCloud." Fox and Mario turned to her. "You'll have your diversion. Sheik and I will infiltrate the station. The ship is yours." Mega Man tossed her a blue capsule and she activated it, opening up another portal.

Upon entering the station, Samus and Sheik crept through a corridor, keeping a watchful eye. Every time they encountered a patrolling Primid, Sheik would take it out quietly or Samus would stun it with her pistol. Once their position was clear, Samus keyed into her earpiece. "McCloud, we'll meet you at the landing pad. And try not to critically damage my ship." "Copy that. See you there. Just gotta watch these turrets."

Surprisingly, Fox's piloting skills had paid off as he had maneuvered through the turret fire flawlessly. The Gunship didn't even have a scratch, much to the bounty hunter's relief. "Alright, team! Let's move!" Fox shouted as he and the rest of the team disembarked the ship. "That core is our priority!"

The team rushed through the station's hallways, noticing dead Federation soldiers who had tried to defend the station valiantly, but failed. "Looks like these guys put up quite a fight." Sonic noted. "But not enough." Samus added. "I hate seeing my old comrades like this. Based on the message, there might be no survivors. Come on, the reactor core should be down this way."

The core, of course, was guarded. The good news was that not many Primids were stationed there, but Fox caught wind of something. "Friend of yours?" he asked Mega Man. The Blue Bomber looked in Fox's direction…and gasped. "Zero?"

The red and white robot strode towards them, his eyes a bright purple. "Zero? No." he responded, whipping out his green plasma blade. "I am… Oblivion. The one who will finish you." Sonic looked confused. "Strange. He doesn't look corrupted, and yet…" "Hacked." Mega Man corrected him as he replaced both his hands with electric points he gained from Spark Man. "His core routines must have been rewritten by the Subspace Army." "Mario, Sonic, get to the core!" Fox ordered. "We'll handle this." Both heroes nodded and headed to the core, with Mario jumping off a series of platforms and Sonic running full-speed towards the core.

"Now to knock some sense into you." Fox said, readying his blaster. Zero charged at the two and swung at Fox, who activated his reflector to block the blow. While Zero was stunned, Mega Man ran in and zapped Zero's chassis, only for Zero to kick him away. Fox fired at Zero, but he countered by deflecting the bolts, with one grazing Fox's shoulder. Gritting his teeth, Fox holstered his blaster and decided to take a more unarmed approach.

Both Mega Man and Fox rushed Zero as he tried to hold them back. Fox kicked Zero in the head and punched him in the torso as Mega Man switched back to his Buster and started to charge it up. Fox rolled out of the way as Mega Man fired, knocking Zero back and making him fall to the ground. Both fighters ran over and knelt down as he stirred.

"Ugh…" Zero groaned, shaking the last of the hacking virus from his systems. His optics fell on Mega Man instantly. "You… the Blue Bomber." He whispered. "W-what happened to me?" Fox helped him up. "You've been hacked. Tried to get rid of us. Had to knock it out of you, so no hard feelings, huh?"

Meanwhile, Mario and Sonic had reached the core, along with a whole bunch of Primids and their commander, donning a plasma rifle and a Beam Sword upon spotting the plumber and the hedgehog.

"Rivals every now and then, but allies for moments like this." The Primid commander spoke. "How quaint." "Yeah, well, it's a long story on how it all started, noodle limbs." Sonic quipped. "So humorous as always, aren't you, hedgehog?" the commander responded. "Once my new master has enough Stone pieces, he shall remake the multiverse in his own image. Thus, he has ordered us…"

A bunch of Primids advanced towards the two heroes and surrounded them in a circle.

"…to destroy any who resist." The commander finished, igniting his Beam Sword. In his alien language, he commanded his soldiers to attack, which they followed with pride.

Both heroes nodded before jumping up to avoid the incoming blaster fire. Sonic balled up and smashed into any Primid close to him with Homing Attacks as they tried unsuccessfully to hit him with lasers. Mario surrounded his fist with flame while airborne and punched the ground hard when he landed, knocking four enemies back with a fiery shockwave. All of them instantly recovered and charged again.

Mario skillfully dodged all Beam Sword swipes and countered with his own punches and kicks, throwing in a Super Jump Punch in the process. Sonic was a literal blue blur as he spun through three Primids, dash-kicked another in the torso and boosted through five more Primids, sending them flying. More surrounded him and aimed their rifles at him, but Sonic jumped at the right moment so that the Primids' laser fire hit themselves instead.

Mario, however, was putting his new skills to the test by tossing Cappy at a Primid and capturing it, turning it against the others with its blaster. Sonic almost bashed that one but stopped once Mario detached himself from it and finished it off by throwing it down a chasm. The two smiled at each other in satisfaction.

"That is one of many problems with the Subspace Army." The commander groaned. "Our soldiers are finely trained, yet they still cannot match you in combat. That will soon change, heroes. Very soon…"

"Not if we prevent that change." The commander turned to see Sheik and Samus standing behind him on two horizontal beams jutting out from platforms. "The bounty hunter and the princess." He said curiously. "I know all too well what brings you here. The Stone."

"Yes." Sheik answered. "And I want you to know that the thing that is your master shall not rule over our universes, for they have their own protectors." "My master is as old as the universe itself. He is a god, a supreme being capable of extraordinary power. What makes you think you stand a chance against him?" the commander asked, readying his blade. Both Sheik and Samus leapt, making the commander ready himself for a strike.

Just as Sheik struck the Beam Sword with one of her knives, Samus wrapped her Paralyzer whip around the commander before slamming him to the ground and tossing him upward, where Sonic spun up and collided with him as Mario threw a single fireball at him. When everything was calm, the Shadow Bugs that remained dissolved away.

"We can be just as powerful as him." Samus answered.

As the strike team approached the space station's core with a now stable Zero, Fox was the first to notice the Stone piece powering attached to the core with maintenance platforms leading to it. "Hmm. Must be important to the core somehow. But what?" "We'll figure out soon enough." Samus stated, holstering the Paralyzer. "Take the fragment, Mega Man."
The robot instantly froze. "I…I don't know." He stammered. "What if I get that same power from when I found a piece in my world? And what if I don't know how to control it? I could accidentally destroy you all with it! I could…"

"Got it!" the group turned to see Sonic holding the Stone piece in his left hand. Apparently, the hedgehog had gotten impatient with Mega Man's hesitation and decided to run and jump up the platforms, nab the Stone piece and hop back down. "Now let's get out of…"
Suddenly, the whole room, if not the whole station, began to rattle violently. Mega Man instantly ran over to a nearby console and examined it. "What's wrong now?!" Fox shouted above the racket.

"I'm detecting massive portal readings directly below the station!" The Blue Bomber yelled back. "The core's not just a power source anymore! The Subspace Army have transformed it into a massive bomb! Full of Corruption Serum! This portal will open in orbit of…" "Uh, dare I ask the target?" Sonic shouted nervously. Mega Man looked back at the console and a horrified expression lit up his face.

"Our base, Smash HQ, at Nintendopolis! We need to hurry! Quick, back to the hangar!" Everyone made a break to the hangar as fast as they could, with Sonic taking point with the Stone piece.