With the last of the turncoat Hunters either captured or having switched allegiances back, Zero returned with the location of Sigma's Fortress. It turned out the Fortress was a mobile, flying fortress, which was why it had been so hard to locate. No one was quite willing to answer Octavia's question of why it was difficult to locate a floating, upside down mountain that wasn't there the day before Sigma began his rebellion.
With X and Octavia fully armed, the trio were immediately dispatched to take down Sigma. Their orders...terminate with extreme prejudice.
As the trio beamed in close to the Fortress, Zero spoke up. "Let's split up," he suggested. "I'll go in first and distract the main defenses, and you two can slip in unnoticed."
X and Octavia both nodded, accepting the plan.
Once Zero had enough of a head start and the sounds of pitched battle reached their ears, X and Octavia began their infiltration. A few Jammingers and Mega Tortoises blocked their path before being blasted, leaving some flying platforms to ascend to reach the Fortress. Once inside, they followed a narrow path with a few rotating turrets, Deerballs, and Gun Volts.
At that point, they climbed several ladders, only to find Vile blocking their path. Zero leapt in. "Stay back you two!" Zero ordered. "I'll take him!" Vile withdrew through a door, with Zero in hot pursuit.
X and Octavia quickly followed, charging in after them, only to hear the sounds of intense battle as they passed through a narrow tunnel. When they caught up, Zero was trapped in a stasis cage - a green capsule using an electrical shield to keep its captive immobilized, via a feedback loop with the captive's own energy source - and Vile was in a new Ride Armor, this one dark purple and grey.
"Do as I say or he's history!" Vile ordered.
"You can take him!" Zero called out.
"Not this time!" Vile barked.
Octavia, for her part, had climbed up to the shoulder of the Ride Armor while everyone was arguing. "Didn't we just do this?" she asked, charging her busters.
Vile turned, and his shoulder cannon blasted Octavia right in the face, blasting her back as she screamed in pain. "I fixed some bugs," he countered.
"Tavi!" Zero shouted out, shattering the stasis cage as he leapt for Vile. X charged in as well, his eyes burning red.
Spinning, Vile seized Zero in one of the Ride Armor's hands and began to squeeze. The shriek of twisting metal could be heard, but Zero focused his gaze on Vile, charging his buster. However, with his buster trapped in the grip and being twisted, the charge resulted in a massive explosion, tearing the Ride Armor apart.
"What the-" Vile began, only to feel two hands grab him, one by his face, the other by his shoulder.
"You hurt Tavi," X growled out as his hands glowed, his white hot fingers thrusting into Vile's eye sockets, boiling his eyes out. "You die!"
X pulled his hands apart, tearing Vile's head from his body. X struggled to get himself under control. "Octavia?" he called out.
"Daddy?" Octavia begged, staggering around, one hoof over her eyes. "I...I can't see anything..."
"I managed to get the energy fields in place," Varia spoke up, "but the plasma interacting with the energy shield caused a bright flare of light, and I didn't have time to get her visor down, too. She's just flash blind."
"Still hurts," Octavia whimpered as X scooped her up.
"T...Tavi?" Zero gasped out.
"Zero!" X rushed forward, Octavia in his arms.
"I'm...I don't think I'm gonna make it..." Zero gasped out. "I'm...I'm too damaged...Auto repair...can't handle it and...the evac circuits...are broken...can't beam out..."
"But...but Uncle Zero..." Octavia whimpered, falling out of X's embrace as she staggered blindly over to him.
One hand reached up, pulling her close. "It's...it's okay, Tavi...I knew this...might happen..."
Octavia blinked her eyes. "But...but I don't...want to lose you..."
"Can't...make it back...in time..." Zero gasped out. "But...you and X...will..."
"Varia!" X suddenly barked out. "How much can your emergency evac circuits beam out?"
As Zero and Octavia turned to X in confusion, Varia beeped a few calculations. "More than just Tavi. Not everything...but with luck, enough."
"Then do it!" X ordered.
"But Da-" Octavia's words were cut off as she and about half of Zero was beamed out.
Once Octavia and Zero were safe back at base, presumably, X charged forward. While numerous enemies tried to get in his way, he blasted them apart...or tore them apart bare handed if he got close enough. When too many got in the way, he released a Pink Charge Chameleon Sting, letting him phase through everything in his way, ignoring everything that tried to stop him.
Before long, he came across a mindless duplicate of Boomer Kuwanger. However, X's patience was short. He had to make his way through to where he could set up a discrete teleport beacon before he could go back to HQ to check on Octavia and Zero, and this doppelganger was getting in his way!
Switching to Launch Octopus' Homing Torpedo, X fired off a few, catching the Boomer Kuwanger duplicate off guard, then charged forward while he was flinching. Seizing the duplicate's horn boomerang, he tore it off and proceeded to drive it repeatedly into the bot's chest until it ceased functioning, before charging onward.
A stray thought flitted through his mind, wondering what the message on his HUD, 'Nega-Freak Mode activated' meant.
Eventually, X reached a large chamber that was the perfect place to set up the teleport beacon, but a large spider mechanaloid was guarding the chamber. It climbed down several poles to try and attack him, before opening an optic to locate him again. Knowing the large red optic would be the only weak point, X leapt forward, tore off one of the spider's legs, and jammed it straight into the optic, shattering it.
He then stood back as the spider bot writhed on the ground, watching for a time. Deciding to make sure, he ripped another leg off before jabbing it in, finishing it off. Once it was down for the count, X set up the teleport beacon and beamed out back to HQ to check on Octavia and Zero.