This is just a OneShot What If that starts before the intro of Mega Man Zero 1. Inspired by these two fics, "Lost in Time, Found By War" by "lunateix" & "Mega Man AXL: Zero Era" by "VirusChris".
Here's the change. What if while trying to track Zero. The Resistance tracks his location to a different location. This is (partly) my interpretation of what happens before Mega Man Zero's opening. The interpretation stops after paragraph 4.
This is my interpretation of Bass and yours may be different. Enjoy the Mega Man Zero x Mega Man Classic crossover. (Wait does that make this some kind of a selfcest crossover because they're the same series but also different series or is this just an average crossover between two properties under the same series name? Leave it in your review and tell me what you think.)
Now this assumes the following.
1. They try finding Zero via tracking his energy signature.
2. Reploids from X and Zero are as strong as X is. X is about as strong as Mega Man or Bass due to him and Zero technically being Robot Masters. So Bass is as strong as X or Zero. This is a major assumption of course.
Ciel was not having the best day today.
First, while trying to locate Zero. They found 2 similar signatures. One slightly stronger than the other, so that's where they looked. Unaware that Neo Arcadia was also looking there for Zero. When Neo Arcadia spotted them they were forced to start running while many of the soldiers who tried to fight died in action.
The worst thing is...
...it was all her fault. That made this hurt the most for her.
They were approaching the location of where they think Zero was sealed. They tracked him to a large skull fortress that looked decayed by time. They ran their way though while the Pantheons chased them. The security system, which was surprisingly still working, despite the old age of the place as the traps began to stop the Pantheons as if they were made for them specifically.
"Gee you think with all the traps this was made for X himself." Milan commented. They were putting some distance between them and the Blue Reploids. But they won't be stalled for long. Their sheer numbers will get them though the security.
Passy then said "Yeah, almost like whoever sealed Zero away wanted to make sure X can't get to him so easily."
Ciel meanwhile wondered why Zero sealed himself up here in the first place.
They come across a large steel door with a frame that says "Dr. W" on it.
Using the time that the traps have given them. They walk up to it and it slides up on its own as they enter and it shuts behind them. They do it again for another door in front of them. One of the two soldiers left stayed behind to guard the doors.
They see a figure dead in the middle of the room It was a Reploid wearing some sort black armor with gold linings. that resembles that of a teenager rather than the adult looking X and Zero. On his chest there is a triangular blue-ish purple crystal with an "F" engraved inside its center. He has purple stripes running down from his eyes and extending down his cheeks. His helmet features large fins that resemble that of a cobra's, giving him a slightly taller appearance than he really it, and a cross-shaped blue jewel on the forehead. He seemed to be broken as his left arm was broken, his legs were gone, almost like they were torn off, his right fin was broken, and a barrage of dents marked his entire body, or what was left of it. He looked like he tried to fight something strong. Finally the jewel on his forehead, was shattered.
There were numbers on a nearby screen.
Operational Capacity: 25%
"Who is this Reploid, he's not Zero?" Ciel wonders.
Milan approaches the robot but is thrown back by a dark energy field.
"Waaa!" He shouted.
Passy only said "It's protected."
Milan only asked "What should I do..."
The soldier guarding the door is shot down by what was left of the Pantheons.
"Waaa!" He shouted.
"Watch out! We are cornered. We have to evacuate now!" Milan shouted as he shot at them.
Ciel looked distraught "But..."
"We have no time to argue!""
Milan was then shot down by a Pantheon's buster shot.
"Arrghh!" He cried out in pain before dying.
"Ciel..." Passy said.
Ciel was silent as she was horrified. Knowing that this was still her fault.
"Ciel!" Passy shouted. Snapping Ciel out of her thoughts with her exclaiming a "Huh?"
Passy suggested "You should use my power! You have no choice!"
"What?! Passy, if I do, you'll be..." Ciel trailed off.
"Don't worry about me. Remember, everyone is waiting for your safe return!"
Ciel thought for a moment "...Okay. Thank you."
"No. I should thank you, Ciel. Good bye..." Passy said as she flew towards the Reploid.
Passy charges towards his dark energy field.
"Passssyyyy!" Ciel shouted as the Cyber Elf flew towards the Reploid. Not only destroying the force field and restoring the robot to his former glory, but also giving her own life to make that happen.
Ciel muttered "He ...has been resurrected... "
The black Reploid got up with a groan, revealing his crimson red eyes as he looked around only to see Ciel, who asked "Who are you? Help me. Please."
He was confused about what she meant only for the sounds of a buster shot to snap him of his thoughts as he turns to the wave of Pantheons a look of confusion before a cocky smirk appears on his face. "Well normally I don't do good deeds like this. But, since I get to smash some tin cans that resemble Mega Man. I won't say no."
His arm then transformed into that of a buster cannon to match their own. Only It made a clicking sound. "Aw Damn it!" He shouted in anger before seeing a small buster gun that was the late Milan's. "Ah, this will do for now."
He then dashed at them before firing a stream of buster shots at them, destroying a few before he kicks one though the chest, followed by smashing one of their heads in.
Ciel watched on as this mysterious Reploid brutally destroyed each of the Pantheons. She had a few questions right now.
Who was the Reploid, why was he nearly killed when they found him, who is Mega Man, why do the Pantheons remind of him of this "Mega Man", and, most importantly, what was his connection to Zero if their energy were so similar.
She was snapped out of thought when she saw him standing on a pile of Pantheon corpses while shouting, "This is the happiest day of my life!" while firing a slew of buster shots into the air.
This made the scientist both really unsettled and relieved at the same time. Unsettled by how this robot was acting, and relieved that the Pantheons were dead.
The Reploid fights through the Pantheons and other enemies with zero mercy, guiding Ciel along the way. They eventually come to a wall.
"What?! It's a dead end... What should we do...?" Ciel asked.
The floor underneath Ciel begins to collapse, as she hurdles towards the ground only for the black Reploid to jump down and catch her. Quickly stopping their speedy decent with a well timed double jump. Which astounded her as that kind of technology was impossible to make.
"You...Thank you... This place seems to be a prehistoric laboratory. We may be able to find a Trans Server, which we can use to go back to the Resistance Base."
"Resistance Base? Trans Server? The hell you talking about?"
As they walk down the hallway Ciel was shocked. He doesn't know about the Resistance or Trans Servers? The latter of the two being famous during the Elf Wars as it was cheaper to make than the standard built-in teleportation technology that Maverick Hunters like X, Zero, and Axl used during the Maverick Wars. Just how old is he?
Before Ciel could ask the question, they see that the hallway is full of rubble. "How nice... This passageway has collapsed in. Shall we go back?"
The Reploid then heard something before he shouted to Ciel, "Stay back!"
A Golem's fist crashes through the debris and grabs Ciel, receding into the next room. The robot chases after it.
Ciel then looks shocked "No! Run... You can't damage this thing with a Buster..."
He then saw that the hole behind finished caving in, leaving him trapped with the Golem.
The robot fires a rapid stream of shots towards the head. Doing some damage before firing a charge shot. It barely did anything.
"Crap!" He shouted.
A nearby computer monitor light up, catching his attention "Huh?"
"...USE THIS... BASS..." a familiar and an unfamiliar voice said.
Ciel overhead the computer, Bass, that was his name?
It threw to him a small computer chip, one that was compatible with his Bass Buster.
"Who or what are you?" Bass wondered in amazement as he put it in.
"HURRY... YOU HAVE TO... SAVE HER... DON'T WASTE TIME..." the voices said.
Bass then was pleasantly surprised by it's power when he took out the golem in one charge shot.
Ciel fell to the ground as it blew it up. As soon as it stopped she said, "I can't believe you were able to destroy a Golem... You may not be Zero, but you're certainly a valuable ally."
"Zero...? Well I'm Bass, the strongest Robot Master alive!" Bass said proudly.
Ciel was confused, "Robot Master? I've never heard of those before. Thank you for saving me though. My name is Ciel. I'm a scientist. Let's go to our base, before more enemies arrive."
They enter the Trans Server room.
"We are in luck. The Trans Server is still active. Stand on the Trans Server and press Control Pad Up, then you can go back to our Resistance Base. Let's go!"
They both teleport back to the base.
And that's it for this story. But I wanna hear how you think Bass would interact with the cast. How would he feel about Copy X, how about Weil and Omega. Either way, I hope you enjoyed this little OneShot idea that was hoping around in my head.