Plasma blasts shot back and forth over the city. The combatants did their best to avoid being struck, but each attack that missed continued eroding away the few buildings that hadn't already been toppled into smoking heaps, providing progressively less cover and occasionally stunning soldiers with stray sprays of pebbles. Two Guardians carefully skirted the edge of the center square, where the fighting was its worst, and stopped when they came to a corner.

"Are you ready?" one of them asked.

"Just hurry up!" the other snapped at her.

The first soldier peered around the corner. The coast looked clear, so she turned around to signal to her partner. Before she could, he was shot in the shoulder.

"Crap!"

Scrambling for her gun, the Guardian locked eyes on the purple Reploid that sat perched on the roof across the street, but wasn't fast enough to predict their next shot—the weapon was blasted right out of her hands, leaving her fingers singed. The two soldiers abandoned the idea of counterattack and prepared to flee, but they realized their chances weren't looking good. The Reploid leveled their gun at them.

A massive ball of plasma rammed into the Maverick from the side, blasting them into at least a dozen pieces. In the direction the shot had come from, someone was bounding from roof to roof with uncanny speed, and they soon dropped onto the street and came to a stop in front of the wounded duo. She was a young Humanoid woman with green eyes and fair skin, with plates of bright blue and pure white armor over her black skintight suit. Where her left forearm should have been, she instead sported a large, cylindrical buster—at least for a moment, until it vanished to reveal a normal arm.

"Are you alright?" she asked, crouching next to the two.

"Not really," said the Guardian with the shoulder wound. "But, thanks for the save, Aile."

"Sorry Commander," apologized the other. "We let our guard down."

Aile smiled at them as she stood back up. "Just don't let it happen again. I'll clear the square, but there might be more coming. As soon as you can, you should fall back and get some first aid."

"Yes, ma'am."

Recreating her buster, Aile dashed around the corner and into the square, firing a flurry of shots as she sailed right past the Mavericks positioned there. She kept going, verifying their destruction by the sounds of explosions and metal scraping the pavement, and rounded another corner into a narrow street. More Mavericks were waiting up ahead. They opened fire immediately, so she jumped to avoid their shots; kicking off the nearest wall, she charged energy in her weapon's barrel as she twisted out of the way of more bullets, and upon touching down she thrust her arm forward and fired. Another massive sphere shot out, plowing through the assembled enemies like they were nothing. Aile rushed past their remains.

"Do you think the civilians all got out?" she asked.

A gentle voice responded, "It's doubtful that all of them made it. Some are probably hiding nearby."

"Yeah, that makes sense. We should look for them."

"Ordinarily I would agree. But, given the circumstances, I think we should leave that to the other Guardians for now, while we focus on the task at hand."

"…You're right. Thanks, Model X."

The city was remote, on the very edge of Legion's territory. So when a call about a Maverick attack went out, there weren't any official security forces nearby to handle it, which the Guardians knew meant it was up to them whether the city's residents lived or died. That was reason enough for Aile, but as they came closer to their destination the crew had picked up something very unexpected on the radar.

We need to find the source of the Biometal signature and disable it, Aile thought. Whether it's a Mega Man or a new Pseudoroid, X and I are the only ones here who stand a chance of defeating it. Once we've done that to ensure the safety of our allies, then we can go back them up.

She launched herself over a high pile of rubble in her path, getting a good look at the street that lay on the other side. There must have once been buildings along it, she thought, but now they had all been decimated. Mounds of mortar and steel fenced in the broken street Aile landed on, making the area feel as if it were cut off from the rest of the city. She was about to get moving again when the sound of footsteps caught her attention. Instinctively raising her buster, she froze and waited.

He appeared slowly from behind a ruined billboard, making no further attempts to hide as he made his way for the center of the street. Aile took the opportunity to size up her opponent: the first thing she saw was the snout of a mechanical horse (one slightly taller than she was), but as it emerged it revealed a human-like torso rising from its back, simulating a rider with the notable exception of a head. Heavy, black armor with red highlights covered the creature, and the yellow eyes of the horse were fixed on her with an eerie knowingness.

When he reached the middle of the street, he stopped. The two of them stood still for a moment, before Aile said, "So it's a Pseudoroid after all. That can't be a good sign."

The Pseudoroid laughed, his mounted torso shaking as if the sound was coming from the headless rider. Pointing, he called out in a deep, gravelly voice, "Aile! It is time for you to despair. Zenull the Dullaroid has come for you, and I will not leave until I have your head!"

"I was the one who came for you, you stupid…" Aile trailed off as the realization sank in. "…You said your name was Zenull? Starting with Z?"

Zenull didn't answer. Instead, he reached up towards the hole where his head and neck should have been—reaching just inside, he took hold of something and pulled, visibly straining as he did. Up out of the torso came a long, segmented strip of metal plates, looking just like a spinal cord, and when it finally came totally free he paused and made a sound like he was catching his breath.

Aile grimaced, her revelation forgotten for the moment. "That's disgusting!"

With a laugh, Zenull flicked the spine, causing the plates to snap together and glow with red light. The energy reached out and solidified, forming a triangular blade of crimson plasma, and he made one swing for show before pointing it directly at Aile.

"That confirms it," Model X said. "This is a Model Z Pseudoroid."

Setting aside her distaste, Aile said, "We've finally found him, then. Okay, X! Let's bring our old friend home!"

Zenull reared back, raising his blade high, and then broke into a full gallop. Aile fired a few shots to see how he would react, but he kept coming without so much as flinching. He was upon her in seconds—he braked hard and swung as he skidded forward, grazing her shin armor as she leapt back and landed just barely out of range. Zenull paused to laugh as she jumped back again for additional distance. Aile started charging energy in her buster, but hung back to see what her foe would do. He ran at her again, and this time she was better able to avoid the slash, countering with a blast that struck Zenull's torso. The Pseudoroid shuddered.

Come on, I know you've got more tricks than that.

A soft chuckle came from Zenull. As he slowly lifted his sword, the blade melted into a thin aura and the "spine" relaxed. When he swung it, the aura extended suddenly and the segments of metal floated down its length, creating a long whip that cut a surprised Aile across the side of her face. Sent sprawling by the blow, Aile rolled back to her feet just in time to avoid Zenull's follow-up attack; she peppered him with shots as he transformed the weapon back into a sword, one of them striking his rear legs. Zenull cried out in pain, making Aile freeze.

"That must be his weak point," X said.

"Which means the more we hit that, the more damage is done to Z," Aile said. "I guess it's been so long I forgot how Pseudoroids work. I'll have to take better aim."

Now recovered, Zenull charged at her once more, sword held high. She shook off the surprise and focused once more on the battle.

"Okay but, of all the things you could've used as a weapon, why would you choose your spine?" Aile asked as she dived out of the way of another slash. "Though, I guess that might've been the idea of whoever made you. Who did make you, anyway?"

Zenull laughed and readied his whip. "Why would I tell you that? The knowledge will be of no use to you in the afterlife!"

Aile dashed, but the attack still managed to make contact. Model X suggested, "We need to put more focus on distance. This area is fairly wide open, and our buster shots have superior range to his whip attack."

"And it's never a good idea to be right in front of anything with a Z Saber," Aile added with a smirk.

Turning her back on the enemy, Aile dashed off as fast as she could. She heard Zenull galloping, but he stopped soon enough—she spared a glance to see him a distance behind her, readying for another charge, but she didn't stop until she reached the barrier of rubble that fenced off the street. Zenull's second charge still didn't get him close enough, only putting him in position for a charged buster shot to stun him. He readied the whip next, and Aile quickly weighed her options. Ultimately, she dashed towards Zenull, managing to completely avoid the lash, and using the extra energy she had stored earlier she unleashed another charged shot at point-blank range. Not waiting to see how he fared, Aile jumped past Zenull and returned to putting distance between the two of them.

The Dullaroid chased her back across the arena once more, succeeding only in taking more charged shots, before pausing suddenly. As he started to laugh, Aile spun to face him, though she still backed away slowly while waiting to see what he was up to. Zenull threw his arms wide, and brilliant red flames burst from the horse's mane and hooves—the torso was instantly hidden in the veil of fire. Aile bumped into the wall. Her foe turned, his eerie yellow eyes now red as well, and leapt.

In a single bound, Zenull was halfway across the area. With a second, he nearly stomped Aile underfoot, only a timely jump onto the wall saving her. However, Zenull bounced onto the wall as well, and when he did, powerful shockwaves surged out from where his feet touched, running through Aile's body and shaking her from her handhold painfully.

Dodging this isn't going to be easy.

Zenull ricocheted back across the area, but then came back at Aile again. This time she waited until he made his second jump, and then rolled aside; the shockwaves didn't reach her, but when Zenull bounced off the wall he angled so that he would pass her, and made a sweeping blow with his sword that cut her along the back. Luckily, once he returned to the far side of the area the flames died down, and the Pseudoroid finally stood still for a few moments.

"Are you alright, Aile?" X asked.

"Been better," Aile replied, getting back on her feet. The wound on her back stung terribly, making it difficult to get into a proper stance. "So here's a suggestion: let's beat him before he uses that attack again. What do you think?"

X didn't respond. Aile got the impression he would be shaking his head if not for the fact of being a disembodied chunk of metal.

Now recovered, Zenull galloped forth yet again. Aile expertly dodged his swing, and the next, and then he readied his whip. When it lashed out, Aile stayed where she was—twisting her arm, she let the whip wrap around her bracer and grabbed the energy weapon. It was a painful maneuver, but it allowed her to reel Zenull in and deliver a charged shot to the horse's face. She pummeled the machine with as many hits as she could before he finally headbutted her to break her grip.

"I thought we agreed to focus on distance?" X said.

Aile shrugged. Brandishing his sword, Zenull said, "You fool! Do you really think putting yourself in such a risky position will bring more benefit than harm? If you are so eager to be rent apart, then allow me to oblige!"

He charged, and Aile dashed. Zenull turned around and prepared to charge again, but Aile didn't seem concerned.

"X," she said. "You're not going to like this, but please trust me."

"I hate it when you say that…"

With a roar, Zenull galloped forth. Aile crouched and waited. The Pseudoroid bore down on her without holding back, but she just sat there, waiting…until she jumped. Zenull stopped and moved into a skid, but the next thing he knew, Aile had flipped overhead and landed on the horse's back behind his torso. It was now he realized her buster was glowing. Zenull tried to slash her, but he couldn't move fast enough: Aile had already pointed her buster at the open hole atop his body, and in the blink of an eye, she fired.

The Pseudoroid was ripped apart in a violent explosion, and Aile was blasted back into the wall. The impact stunned her for a moment. When she had her senses back, she stood and surveyed the wreckage, spotting Zenull's head lying a few meters away.

"Impossible…" he croaked. "I am the bringer of death…how could I be the one…to die…?"

A second later, the light was gone from his eyes. Aile turned, saying, "We need to find the legs…"

There was a bright flash at the edge of her vision. She hopped towards a pile of scrap metal that was pulsing with light, and just as she was about to dig through it, something shot up out of it to float at about eye level. The compact object was made of black, white, red, and green metal, with a design on the front that resembled a face. Aile gaped for a moment, but then her expression broke into a huge grin.

"Model Z," she whispered.

In a flash, Aile dropped out of her Megamerged state. Her clothes beneath were still blue and white, but now her long brown ponytail was free to fall behind her. Model X appeared in the air next to her, a piece of blue metal similar in design to Model Z.

"It's been a while, Z," X greeted.

"Sure has," Z said. "Heck of a greeting, too. Did you have to blast it right in the weak point?"

"Ah, sorry about that," Aile said, chuckling sheepishly.

"Oh, you've survived worse," X said.

"Fair point," said Z.

Aile stepped forward. "It's really good to see you again, Model Z. Sorry it took us so long to track you down."

"No, that's not your fault. A lot happened after we parted ways…but, maybe now isn't the time."

X turned back to Aile. "He's right. We've got to finish cleaning up the Mavericks and make sure the townspeople are safe."

Aile nodded. "We'll catch up back at HQ when this is over. Model Z, why don't you rest for now? X and I can handle things."

The Biometal seemed to consider this for a moment, before ultimately saying, "Think I'll take you up on that."

Taking both Biometals, Aile stored Z in her pocket and held X out. "Megamerge!"

With her armor back, Aile dashed over and scaled the wall of rubble, making her way back to where the other Guardians were, keeping her buster ready.

Finally, she thought. Now maybe we'll get some answers.

Grey barreled down the hall of the Guardians' airship, bursting through the door labeled "LAB". Standing at the computer console inside were Aile, who looked a bit surprised but ultimately smiled, and a short elderly man with a long white beard, who just scowled.

"Is it true?" Grey asked. "You really got Model Z back?"

Aile nodded, and then gestured to her side. Model Z floated up to hover above her hand, saying, "Good to see you again, kid."

Grey rushed forward excitedly, saying, "This is great! With you, Aile can get back to full power, and we can go on the offensive! And you probably know what happened to the others after Ouroboros, right?"

"We were just getting to that!" the old man said, shoving Grey back. "Honestly, must you be so loud?"

"It's no big deal, Fleuve," Aile chuckled. "We're all pretty thrilled—there's no harm in celebrating a little, right?"

Fleuve grunted. "I'll celebrate once this is all over. Now…" He sank into a rickety-looking chair. "Model Z, I've been able to repair most of the damage you sustained. I'll still need a few E-Crystals to finish the process, though, so don't go trying anything crazy just yet."

Model Z turned slightly. "We'll see."

Aile faced the Biometal, her face growing serious. "So, Model Z…can you tell us what happened?"

"Well," Z sighed, "after the kid beat Ouroboros, everything started to collapse. The four working for Albert managed to get out, but I didn't quite make it. I was sealed in the ruins when they fell underwater. Not really sure how long I was there, but eventually, someone came and found me."

Aile nodded. "And that person was?"

Model Z looked right at her. "It was Master Thomas."

She gritted her teeth, hissing, "Damn. I didn't want to be right."

"No way…" Grey said. "Really? You're sure it was him?"

"Positive," Model Z said.

Another piece of Biometal appeared from behind Grey. "Th-then, all those rumors we've been hearing are true? About Legion ignoring Maverick attacks, and what happened to Master Mikhail?"

"I don't know what all you've heard, Model A, but Thomas is definitely our enemy. He's the one who stuck me in that ridiculous horse Pseudoroid, and the other four Mega Men are working for him—might've been working for him all along, I can't really say. But you'll see for yourself soon. The reason Thomas unleashed Zenull was because he wanted to draw out Aile, and now that he has, he's going to set the next phase of his plan into motion."

Aile crossed her arms, glaring at the floor as she processed the information. "…If he wanted me to have Model Z back before kicking things off, that's awfully bold. He must think this is a solid plan."

"Model Z," Fleuve said, "is there anything more you can tell us? What is Thomas's plan anyway?"

"Afraid he didn't tell me much else," Z said. "All I know is that things are about to get rough, and that he wants to 'reset the world', whatever that means."

"Sounds just like Albert," Grey said. "Maybe Model W got to him too?"

"But we destroyed all the Model Ws when we destroyed Ouroboros, didn't we?" Model A asked.

"Maybe," Z said. "But if the hatred powering Model W was easy to kill, it wouldn't have turned into a Biometal in the first place. We can't rule anything out yet."

Aile turned to Grey. The Reploid boy stood with his fists clenched and his eyes shut, hunching over and shaking very slightly. "Grey. Are you alright?"

"What am I gonna tell the Hunters?" he asked. "We've been taking so many jobs from Legion, and now, it turns out we've been helping our enemy all this time? I don't know what we're going to do."

Fleuve shrugged. "You're Hunters. If Legion's still paying you well, you'll keep at it."

Grey whirled on Fleuve. "Right, because Hunters only care about money, is that it?!"

"Well, you don't see the Guardians charging the people we save."

"Don't act like you've never taken payment for a job! If the Guardians do more free work, it's only because you're always in hiding—Hunters have saved just as many people, if not more!"

Fleuve started to get up, but Aile stepped between them. "That's enough! We can't afford to keep bickering like this!"

Leaning back, Fleuve grumbled, "It's not like they stopped cooperating with Legion the first time we warned them…"

Aile shot a quick glare at Fleuve. Turning back to Grey, she said, "I'm sorry, Grey. But we can't change what's already been done. What we need to focus on now is preparing to fight whatever Thomas has cooked up."

Grey slowly relaxed. "…Fine. I'll try telling the other Hunters, but I can't guarantee they'll all believe me." Glaring at Fleuve, he added, "Don't blame me if some of them keep taking Legion jobs."

"Actually, it might work to our advantage if they do."

Everyone turned to look at Aile. "What?" Model A asked. "We find out that Thomas is trying to destroy the world, and you want us to keep doing business with him?!"

"I don't want to arouse his suspicions if we don't have to," Aile said. "Of course, he knows about you and Grey, so that might already be out the window…but there's a chance he might still try to manipulate you and the other Hunters to his advantage. If he does, and if you play along, it could give us an opportunity to outsmart him."

Grey averted his gaze. "…I guess I'll consider it."

Before Aile could say anything else, the door burst open once again, this time allowing a Guardian into the room. "Commander Aile! Sorry for the intrusion, but it's an emergency! We've picked up another distress call, and…"

As the Guardian tried to catch her breath, Aile said, "Alright, well, set a course."

The Guardian shook her head. "We already did, ma'am, but I had to inform you because…it's a Guardian signal…"

Aile nodded slowly, still not understanding why she was so flustered. "Okay. Which squad sent it?"

"It's not a squad. This signal…it's Priority Zero!"

Instantly, Aile's eyes shot wide. She started forward and said, "R-Really?! You double checked it?"

"Triple checked it, ma'am! It's the real thing!"

Aile ran out the door, shouting back, "We'll talk more later, Fleuve!"

"Priority Zero?" Model A repeated. "What's the big deal about that?"

"Got me," Grey said.

As he went back to work, Fleuve said, "A Priority Zero call can only be sent out by the Commander of the Guardians."

Grey looked at him sideways. "What? But Aile's already here."

"I suspected she hadn't told you. Aile is the Acting Commander. She's been filling in ever since the real Commander left for a special mission years ago."

Model A and Grey exchanged a look. "So," Grey said, "then this call must be the real Commander, I guess?"

Not waiting for a response, he headed to the bridge to see Aile issuing orders. Looking up at the radar map displayed on the main screen, she grinned, and said, "Give the engines whatever you can—full speed ahead! It's finally time to rendezvous with Prairie!"

Notes:

This is something I've had in the back of my mind for a while now. It's been sitting in my computer gathering dust, and I don't think this first chapter is going to change much beyond this point, so I figured, what the heck, post it. Besides, this'll let me see if anyone's interested in this story and that'll be some incentive to progress. Even if I do move on with this, though, it might not be quick since my first priority is going to remain my Star Force fanfic, Shooting Star Sonia. So, with all that out of the way…obligatory ZX3 fic!

"Termination" was chosen for similar reasons to why ZXA went with "Advent", plus this is meant to be the endpoint of the ZX series. As an added bonus, "ZX Termination" sounds like "Extermination" when you say it! Also, apologies for the generic summary. Maybe as the plot progresses I'll come up with something better, but for now that'll have to be enough to get the point across.

For clarity's sake, I'm sticking with Aile and Grey—Vent and Ashe don't exist here. It'd be a hassle to juggle both pairs, Aile's the best, and I think Grey will give me more to work with. And Grey's going to be more of a supporting character, too; since this series started with Aile, I want to end it with Aile.

A Model Z Pseudoroid seemed like a good place to start. We needed Z back somehow, but it couldn't be too easy. Zenull is based on the Dullahan, an Irish myth about a headless rider who uses a human spine as a whip, and calls out a person's name at the instant of their death. I figured a Pseudoroid made out of Zero needed to be edgy as hell.

Revealing Thomas does feel a bit quick, but it's something we all know so I figured it best to get it out of the way. The details are going to be the real mystery.

Right, so Prairie. ZXA made Aile out to be the new Commander and implied that Prairie might be dead, but I didn't like the idea of her being killed off-screen, so the Acting Commander bit is my way of dancing around the issue. This will also provide an opportunity to answer a few other questions relating to ZX's backstory, but you'll see what I mean when we get there.

And that's chapter one. Not sure when chapter two will be done, but hopefully it won't take too long. I think you'll be surprised to see who the next mission's boss is!