On the city's streets, Wario blasted the Subspace monster with his Bob-omb Cannon repeatedly, shouting as he did so. The beast was currently snapping its jaws at Mega Mario, who stepped back to dodge it and countered by slamming his fist right in its mouth, knocking a few teeth out. The monster rammed its head into the plumber, making him stumble. Turning to Wario and Luigi below it, it let out a massive roar that blew saliva into Wario's face and blew Luigi's hat off his head as he screamed in terror.
As Luigi scrambled for his hat, Wario wiped his face, grumbling before firing another Bob-omb right into the creature's mouth, making it roar in pain. Wario squeezed the cannon's trigger again, only to hear a loud click. He was out of ammo. Behind him, Luigi trembled in fear before noticing a blue light shining from the top of Smash HQ: the 'return to base' signal. Both of them turned and ran as fast as they could, with Luigi zigzagging to avoid pieces of raining building debris from the giants' clash. Eventually, the two found their vehicles (Luigi's being a standard green Mario Kart racing bike with his 'L' insignia) just a block away and, without hesitation, climbed on and gunned the engines before racing away back to base.
Mega Mario was holding his ground as the beast lunged for him again. Ducking a claw swipe one moment and punching it in the jaw another, Mario knew he had to disengage when he saw Smash HQ's beacon. Grabbing the monster's throat, slamming it to the ground and kicking up dust, Mario turned and began to stomp down the street in a running motion as he felt the Mega Mushroom's effects starting to wear off.
In another golden flash, Super Sonic struck the Subspace monster from multiple directions, flying around its jaws like a bright mosquito. After landing a few more hits, Super Sonic zoomed towards Smash HQ as he left the enraged beast behind, hoping the last of his ring energy would be enough to get him there. Avatar used his grapple glove to traverse through the neighborhoods, trying his best to keep up.
Donkey Kong and Bowser jumped from rooftop to rooftop, with the ape having to jump over antennas, climb the side of buildings and swing on horizontal flagpoles. Charizard beat his wings as he flew to HQ, with Yoshi riding on his back with a hand pointing to the base. The four Arwings and the Mii Force fighter accompanied them as they wove and barrel-rolled between skyscrapers. Samus' Gunship was already beginning its landing sequence. The rest of the Smashers who couldn't fly, use a vehicle or travel fast enough had to go by a short-range portal that would deliver them to the top floor of the building.
On Smash HQ's landing pad, Super Sonic reverted back to his normal blue self and Mega Mario shrunk back down to size as he jumped up to the platform. The Arwings and the Mii Force fighter joined Samus' Gunship on the pad as they finished their landing. Beside the rest of the Smashers were the recovered Smash Stone fragments.
"The Smash Stone is a source of unimaginable power." Ganondorf explained his plan to everyone. "Even with just a single fragment, we can tap into that power." Mega Man seemed concerned as he and Zero stepped forward. "But what if we can't control it? Wouldn't it destroy us?"
"There is no other choice." The warlock answered. "We must use this power, or else we are all finished." Mario strode forward and picked up one of the red-blue crystals, staring at it in his palm. Luigi approached from behind and laid a hand on his brother's shoulder. "You a-got this, bro." he reassured, but as Mario nodded, he couldn't help but notice a hint of uneasiness in Luigi's tone, as if he might lose his brother for good. Mario patted him back before a booming sound from the sky made everyone look up.
From the streets below, the Subspace monster roared in fury as it approached Smash HQ's courtyard, shrugging off all of the laser turret defenses. From above, the Corruption Serum bomb rocketed down like a meteor, already burning up from the fall. Robin and Mewtwo concentrated again, focusing their magic and psychic power to redirect the bomb's course, so it would collide with the monster.
Mario walked to the edge of the platform before looking back at all of the Smashers behind him. They nodded, indicating that the time had come to use the Smash Stone's full potential. Mario turned back around, looking at the small crystal in his hand while hearing the beast come closer and closer.
This was it…it was now or never.
Mario clenched his fist and immediately felt his body in massive pain as the crystal erupted in a flash of light. An unexplainable force racked him from the inside and he collapsed to the ground. His entire body began to surge with cosmic power and glow a bright red and blue. He could feel the intense stares of everyone on him. It was like the first time he had used a Smash Ball, only a hundred- no, a thousand times stronger!
Gathering his strength, Mario rose to his feet and opened his eyes, which were now a bright yellow. It was like his body was supercharged, in control of a more supreme force. He felt like a god. A master of the multiverse. Was this how Master Core felt like all the time?
Baring his teeth, Mario drew his arms back, which began to burst into flame. As the fire expanded in strength, Mario did his best to keep it held within him until the time was right. But he couldn't hold it much longer. If he didn't unleash it soon, his body would be overcome by the Stone fragment's power. He would be destroyed from the inside out.
The bomb plummeted down to the surface as the Subspace monster leapt to the landing pad. Mario's eyes began to surge with power. Almost…almost…
"NOW!" everyone yelled as the bomb flew right into the beast's path.
Mario thrust his hands forward with a scream. Fire erupted in a beam-like projectile that struck the bomb and sent it into the monster. As the bomb exploded and the beast let out a dying roar, the last thing Mario heard before his world turned white were the echoes of both Peach and Luigi calling out his name…