Previously on Mega Man X: Maverick Buster...
X & Alia returned to the remains of Sigma's Palace, where X began his search for Zero, while Alia stood guard. Sneaking through the rubble and damaged Mechaniloids, X was ambushed by a Reploid bounty hunter called Spider, who wanted Zero for his client. X's fight with Spider finished as quickly as it started, as Spider disappeared during an explosion! But that was when former Maverick Hunters Wheel Gator & Bubble Crab attacked X...
While Alia was standing guard outside, she had Layer back in Hunter Base scan a strange device she found near the entrance... Not only was it a bomb, but there were dozens of them all over the slanted island! After X escaped from the Mavericks, he found a Light Capsule that gave him the power to fire TWO Charge Shots at once! And he used this power to defeat the Mavericks and copy their abilities before Sigma's Palace exploded!
Meanwhile, Zero was busy fighting off what enemy Mechaniloids he could, when he came across a familiar face... "Sigma?!"
How is Sigma still alive? Can Zero fight him without X? What happened to X when Sigma's Palace exploded? Find out next in Mega Man X: Maverick Buster!

Mega Man X: Maverick Buster
Season One: The Search for Zero

Episode 4 - Chapter Four: The Truth About Heroes and Villains

Alia managed to get herself away from Sigma's Palace just before it exploded, but she was worried about X...
"X. X, do you copy?" She asked with her hand over her ear, before raising her other wrist up to her mouth. "Layer, are you still tracking X?"
"*bzz* I am... but he just teleported, and I'm struggling to- found him!" Layer replied, making Alia sigh with relief. "He's in what's left of Abel City, which is currently under Maverick attack. *bzz*" This information confused Alia.
"Why did X go there?" She asked herself. "In fact, why are there Mavericks there?"

Meanwhile, X had just teleported into the ruins of Abel City, where he felt a great deal of relief.
"Huh... that was close..." He thought, before having a look around. "Abel City? What am I doing here?" Suddenly, X spotted a large green tank driving past, blowing up more of the ruins and deploying flying Mavericks as it past X. "Wait... that's Wheel Gator's tank! Did he survive the explosion, too?" Just then, X also noticed that the tank started blowing up from the inside, which made him think that someone he knew was onboard... "Zero..." X then started chasing after the tank, hoping to find Zero inside...

There was a Reploid destroying the tank from the inside, but it wasn't Zero... it was a massive Reploid, who was covered with heavy gold and dark-green armor, and was armed with a massive laser axe. This Reploid was slicing his way through many enemy Mechaniloids, aswell as vaporizing some of the hull with his laser eyes!
"You cannot stop me from saving Massimo! RRAGH!" The Reploid yelled as he continued his battle through the tank... until he found a cell with what appeared to be a skeletal Reploid inside. "Massimo! I finally found you!" After the big Reploid broke through the bars of the cell, he attempted to reach for the skeletal Reploid, but it stopped him by holding its hand out. "Sir? What's the matter?"
"Go... you must *gasp* leave me..." It said.
"But... Massimo..."
"No... my time as the legendary Steel Massimo *gasp* has come to an end..." The skeletal Reploid then pointed to the bulky Reploid. "Now... it is your turn... *gasp* Steel Massimo..." This made the bulky Reploid uncomfortable.
"But... there's still so much I don't know! I am not worthy of being the next Steel Massimo!" The skeletal Reploid then placed his hand on the bulky Reploid's chestplate.
"This armor... only attaches to Reploids... it finds worthy... and you, Massimo... are worthy of carrying the mantle..." At that moment, the skeletal Reploid started to disintergrate in front of Massimo from the feet up.
"Massimo!"
"I believe in you, my son... Good luck... Steel Massimo..." Just after he said that, the skeletal Reploid was nothing more than a pile of ash.

Just seconds after grieving over his predecessor, Massimo was filled with a massive amount of anger... which was when he caused the prison cell to explode, getting the attention of several Mavericks... and X, who got a glimpse of Massimo.
"Was that... Steel Massimo?" X asked himself as the bulky Reploid disappeared from his sight. As X started blasting at the tank from the outside with his twin Busters, Massimo was slicing and blasting his way through the tank once again. Except this time, he was furious.
"YOU WILL ALL PAY FOR KILLING THE LEGENDARY STEEL MASSIMO! RRAGH!" He screamed in anger, as he pounded on the floor, which suddenly made the tank go faster for some reason. Because the tank was accelerating, X started to fall behind. But he saw where it was headed; a volcano.
"Alia, do you read me?" X asked as he held his hand over his ear.
"*bzz* X, you have no idea how relieved I am to hear your voice!" Alia replied. "What are you doing in Abel City? *bzz*"
"I'll explain later." X told her. "Listen, I think I've found a lead for Zero... can you rendezvous with me at Mt. Magma?"
"*bzz* Sure. I'll meet you there with some backup, X. *bzz*" After that, X started chasing after the tank again. But soon after he did, the tank exploded after crashing into the volcano!

Meanwhile, Zero had just reunited with a Reploid believed to have been destroyed by X...
"S.. Sigma?!" He asked the large Reploid, who merely smirked in response. Coming back to his senses, Zero then aimed his Buster at Sigma. "I guess X wasn't strong enough, after all..."
"Oh, but he was, Zero..." Sigma replied, as he revealed his Laser Saber. "And like you, I must thank the X-Hunters for bringing me back into the land of the living..." This startled Zero.
"X-Hunters... who are they?" Asked Zero, making Sigma chuckle.
"You'll find out... if you can defeat me!" After saying that, Sigma leapt towards Zero and slashed at him with his Laser Saber, but Zero backflipped over it! Once he was far enough away, Zero fired three weak shots at Sigma, but he just used his Saber to deflect them.
"Take THIS!" Zero shouted as he fired a full Charge Shot at Sigma, which knocked him back a little.
"Is that all you've got?" Asked Sigma, as Zero fired more weak shots his way, but he deflected them again. This allowed Zero to fire another Charge Shot his way... while it did bounce Sigma back again, Zero dashed towards him with determination in his eyes.
"Shoryuken!" Zero shouted as he punched Sigma in the chin with a ice-cold fist, knocking him back even further!

"Is that all you've got, Sigma?" Zero teased, before he heard Sigma chuckling as he slowly got to his feet.
"You don't even know all that I've done before being classified as a Maverick, do you Zero?" He asked, confusing Zero.
"Really?" Zero asked back, feeling somewhat cocky. "Then enlighten me. What else have you done to make people think you're Maverick?"
"Let me put it this way... why do you think Repliforce turned on the Maverick Hunters after so many years of being your allies?" This made Zero remember the horrific moment in history when he, X & the Maverick Hunters were at war with Repliforce... and Zero was forced to fight the one Reploid he cared about the most...
"Iris... no..." Zero muttered as he fell to his knees, overwhelmed with emotion, before placing his hands over his eyes. "Iris... Colonel... no... we didn't have to fight each other... IRIS!" After the scream that made Sigma smirk again, Zero got to his feet and aimed his Buster at Sigma. When Zero started charging up energy, his eyes with filled with tears of anger and sadness. "YOU MADE ME KILL HER, YOU BASTARD!"

When Zero fired his Charge Shot, he quickly dashed after it, aswell as firing weaker shots into the Charge Shot to make it bigger. Sigma felt a serious stinging as electricity was flowing all around his body after being hit by Zero's Charge Shot. This allowed Zero to grab Sigma's Laser Saber, and he slashed at Sigma's arm, but the Maverick blocked Zero's attack with claws coming out of his knuckles!
"You thought I wouldn't be ready to be disarmed?" Sigma asked with a smirk, as he stared at Zero, who was furious.
"Rrrrgh! Rasetsusen!" Zero shouted, as he started spinning in the air with Sigma's Laser Saber above his head. This attack was just creating a lot of sparks between the Laser Saber and Sigma's claws, so Sigma shoved Zero away.
"What are you waiting for, Zero?" Asked Sigma, before signaling Zero to get closer. "Come and get me..." Zero then started dashing towards Sigma, making the Maverick defend himself.
"Raikousen!" Zero yelled, which made him disappear from Sigma's sight. When Zero reappeared, a bolt of lightning had passed through Sigma from the Laser Saber, paralyzing Sigma in the process. This made Zero jump up the wall that was closest to Sigma before making another jump above Sigma's head. "This is for Iris... Enkoujin!" Just before Zero started falling towards Sigma, he shoved the Laser Saber between his legs as it had just started emitting a flame from its tip. Once Zero landed on Sigma's shoulders, the Laser Saber had pierced Sigma's skull, causing him to spasm out before his body fell apart into flames!

"Hmph! Good riddance." Zero said after pulling the Laser Saber out of Sigma's head, and sticking in a slot in his back. "I've gotta get outta here and find X. He'll want to know about this..."
After Zero ran away from where he defeated Sigma, the Maverick's burning remains started to shake. Suddenly, a holographic image of Sigma's face is seen on a nearby screen. When the screen flashed green, all of the pieces of Sigma's body re-assembled & repaired themselves... and Sigma opened his eyes before smirking once again!

END OF CHAPTER

NOTE: In Maverick Buster, the events of Mega Man X4 happened prior to Mega Man X1/Mega Man Maverick Hunter X. The only difference is Sigma never revealed himself to be the mastermind behind Repliforce's rebellion until now.