The morning after his induction into the Justice League—provisional induction, as Batman kept reminding everyone—Build woke up with a singular thought burning in his mind like a star going supernova.
He needed to experiment.
The Build Driver was, at its core, a device built on the principle of scientific exploration. Sento Kiryu had been a genius physicist who constantly pushed the boundaries of what was possible, creating new FullBottles, discovering new Best Matches, and evolving his power to meet ever-greater threats. The Driver was designed to grow, to adapt, to become more than the sum of its parts through the application of creative thinking and rigorous experimentation.
And Build—the former Takeshi Yamamoto, now reborn as the wielder of the most scientifically advanced transformation system in any universe—had ideas.
So many ideas.
He sat up in bed, his mind already racing through possibilities. The quarters the League had provided were comfortable but sparse—a bedroom, a bathroom, a small kitchenette, and a living area that was currently dominated by the growing pile of notebooks he had filled with theoretical formulas and Best Match combinations during his sleepless hours.
The FullBottles sat on his nightstand, arranged in neat rows according to category. Organic bottles on the left—Rabbit, Gorilla, Hawk, Ninja, Dragon, Phoenix, Octopus, and a dozen others. Inorganic bottles on the right—Tank, Diamond, Gatling, Lock, Comic, Rocket, and their mechanical brethren. Each bottle glowed faintly with internal energy, the essences within responding to his proximity like pets recognizing their owner.
Build picked up the Rabbit bottle and turned it over in his hands, feeling the familiar thrum of speed-essence against his palm. Then he picked up the Ninja bottle with his other hand, feeling the subtle whisper of stealth and precision.
Rabbit and Ninja were not a Best Match. Not in the traditional sense. The show had established that Best Matches were specific combinations that resonated with each other on a fundamental level—Rabbit with Tank, Gorilla with Diamond, Hawk with Gatling. Mixing bottles outside of these established pairs produced Trial Forms, which were functional but suboptimal.
But Build had been thinking.
The Best Match system was based on the principle of complementary opposites. Speed and power. Flexibility and hardness. Stealth and firepower. The bottles worked best when they balanced each other, when the strengths of one compensated for the weaknesses of the other.
But what if he could create new bottles? Bottles that combined the essences of existing bottles into something new? Bottles that were themselves Best Matches, containing within them the perfect balance that normally required two separate components?
What if he could make hybrid FullBottles?
The thought had occurred to him during his testing with the Justice League. When he had used NinNinComic, he had noticed something interesting—the two organic bottles (Ninja and Ninja—yes, the form used the same bottle twice) had resonated with the inorganic Comic bottle in a way that felt different from normal Best Matches. There had been a harmonic, a frequency, a scientific principle that he couldn't quite articulate but absolutely felt.
What if he could capture that harmonic? Bottle it, literally? Create new essences that contained the combined properties of multiple sources?
There was only one way to find out.
Build got out of bed, got dressed in his now-familiar white lab coat, and went to find a laboratory.
The Justice League, as it turned out, had laboratories.
Many laboratories.
An almost excessive number of laboratories, actually, scattered across their various bases and facilities like a mad scientist's idea of interior decorating. There were chemistry labs and physics labs and biology labs and xenobiology labs and dimensional research labs and temporal mechanics labs and at least one lab that seemed to exist solely for the purpose of studying the effects of various types of radiation on cheese.
Build did not ask about the cheese lab. Some questions were better left unanswered.
The lab he eventually claimed for his own was located in the basement of the Metropolis facility where he had first met the League. It was a mid-sized space, previously used for analyzing recovered alien technology, equipped with sensors and fabrication equipment and enough raw materials to build approximately three and a half spaceships.
Cyborg had helped him get set up, clearly fascinated by the prospect of studying the Build Driver's technology.
"The energy signatures are unlike anything I've ever seen," the half-machine hero said, watching as Build arranged his bottles on a newly-constructed workbench. "It's not electromagnetic. It's not nuclear. It's not any form of exotic radiation I can identify. It's like... pure concept, somehow converted into a physical medium."
"That's exactly what it is," Build confirmed. "The FullBottles contain essences—the fundamental nature of whatever concept they represent. The Rabbit bottle doesn't just give me rabbit-like abilities. It contains the platonic ideal of 'rabbit,' distilled into a form that can interface with the Driver's transformation matrix."
"That shouldn't be possible."
"And yet." Build held up the Rabbit bottle, letting its red glow illuminate his face. "Here we are. Science fiction becoming science fact. Or maybe science fantasy. The line gets blurry when you start dealing with conceptual essences."
Cyborg's organic eye narrowed thoughtfully. "You said you want to create new bottles. How would that even work? Where would the new essences come from?"
"That's what I'm going to find out."
Build pulled out a notebook—one of the many he had filled during his sleepless nights—and flipped to a page covered in diagrams and equations.
"My theory is that the FullBottles aren't just containers. They're more like... seeds. Each bottle contains a kernel of essence that can grow, evolve, combine with other essences under the right conditions. The reason Best Matches work is because certain essences are naturally compatible—they want to combine, on a fundamental level."
He pointed to a diagram showing two bottles merging into one.
"If I can identify the specific frequencies of each essence, I should be able to create resonance chambers that encourage combination. Essentially, I'll be wedding two essences together, creating a hybrid that contains the properties of both."
"And you think this will work?"
Build grinned. "Only one way to find out. That's the beauty of science, right? Hypothesis, experiment, observation. If I'm wrong, I'll learn something. If I'm right..."
He trailed off, his eyes gleaming with anticipation.
"If I'm right, I'll be able to create Best Matches that have never existed before. Forms that combine abilities in ways that shouldn't be possible. Powers that exceed anything the original Build Driver was designed to produce."
Cyborg was silent for a moment, processing this information.
"You're talking about exponential power growth," he said finally. "Theoretically unlimited potential."
"Theoretically, yes."
"That's terrifying."
"That's awesome," Build corrected. "There's a difference."
The first experiment was relatively simple.
Build selected two bottles that he theorized would combine well: Tank and Comic. The Tank bottle contained the essence of armored warfare—power, durability, relentless forward momentum. The Comic bottle contained the essence of illustrated storytelling—narrative flexibility, visual dynamism, the ability to bend reality in ways that made aesthetic sense rather than physical sense.
In normal circumstances, these bottles were not a Best Match. Tank paired with Rabbit for the standard RabbitTank form. Comic paired with Ninja for the NinNinComic form. Using Tank and Comic together would produce a Trial Form—functional but unbalanced.
But Build wasn't trying to use them together. He was trying to merge them.
He had constructed a resonance chamber from the lab's available materials—a cylindrical device approximately the size of a refrigerator, lined with sensors and energy conductors and focusing crystals that he had calibrated using the Build Driver's own frequency patterns. The theory was that the chamber would create an environment where the two essences could interact directly, unmediated by the Driver's transformation matrix.
"Recording experiment one," Build announced, activating the lab's audio/visual logging system. "Attempting to create a hybrid FullBottle by combining Tank and Comic essences. Predicted outcome: a new bottle containing properties of both parent essences, specifically combining Tank's durability with Comic's reality flexibility."
He placed both bottles inside the chamber and sealed the door.
"Initiating resonance sequence."
The chamber hummed to life, energy patterns swirling through its internal structure. Through the observation window, Build could see the two bottles beginning to glow—Tank with blue light, Comic with purple—the essences within responding to the chamber's influence.
For a moment, nothing happened beyond the glowing.
Then the bottles began to vibrate.
The vibration intensified, the glow brightening, the hum of the chamber rising in pitch. Build watched, transfixed, as the two colors began to bleed into each other, blue and purple mixing and swirling like paint in water.
The chamber's readings spiked. Energy levels shot up beyond the sensors' calibrated ranges. Warning lights flashed. Alarms blared.
And then, with a sound like a champagne cork crossed with a thunderclap, the process completed.
Build opened the chamber door, waving away the smoke that billowed out. Inside, where two bottles had been, there was now only one.
It was beautiful.
The new bottle was larger than standard FullBottles—about twice the size, with a more complex internal structure visible through the transparent casing. Its color was a deep indigo, the perfect midpoint between Tank's blue and Comic's purple. The liquid essence inside swirled with patterns that looked like comic book panels—action lines and dramatic angles and bold outlines, all rendered in varying shades of metallic blue.
Build picked it up, feeling the weight of it in his hand. The essence within responded to his touch, and he felt a sensation like nothing he had experienced before. It wasn't just power or speed or stealth. It was narrative weight—the sense that whatever he did while using this bottle would be dramatic, impactful, aesthetically perfect.
"ComicTank," he breathed. "Holy shit, it actually worked."
He shook the bottle, watching the essence swirl. The internal pressure felt enormous—not dangerous, but potent. Like holding a compressed star.
"I need to test this immediately."
The testing arena was empty when Build arrived, which was perfect. He didn't want an audience for this—not because he was afraid of failure, but because he was afraid of succeeding too spectacularly and accidentally destroying something important.
He stood in the center of the arena, holding the ComicTank bottle in one hand and staring at the Build Driver on his waist.
Standard Best Matches required two bottles—one organic, one inorganic—inserted into the Driver's two slots. But ComicTank was a hybrid bottle, containing both essences in a single container. Would the Driver even accept it? Would it know how to process a combination that existed outside its original parameters?
There was only one way to find out.
Build inserted the ComicTank bottle into the right slot of the Driver. Then, after a moment's hesitation, he inserted the Rabbit bottle into the left slot.
The Driver's standby announcement played:
RABBIT! COMICTANK!
Build's heart was pounding. The Driver had accepted both bottles. It recognized the hybrid as a valid component. Now came the real test.
He grabbed the Vortex Lever and cranked it.
KAGEKI NA FINISH! RABBITCOMICTANK!
The transformation hit him like a freight train made of pure awesome.
Energy exploded outward from the Driver, mathematical formulae and scientific notation swirling through the air in patterns more complex than anything he had seen before. The armor materialized in sections—first the left side, red and rabbit-themed as expected, then the right side...
The right side was indigo, the exact shade of the ComicTank bottle. But where normal Tank armor was angular and military-styled, this armor was stylized—bold lines and dramatic contours that looked like they had been drawn by a master comic artist rather than engineered by a scientist. Panel-like segments divided the armor into action-scene compositions. Speed lines seemed to trail from the edges even when he was standing still.
The helmet was particularly impressive. The right eye was rendered in comic-book style—exaggerated and expressive, with thick outlines and dramatic shading. A small tank barrel extended from the right side, but it was stylized too, looking more like a manga weapon than actual military hardware.
Build looked down at himself and felt tears welling up behind his eyes.
"This is the most beautiful thing I've ever created," he whispered. "I am a genius. An actual, literal genius."
He tested the armor's capabilities by running a lap around the arena. The Rabbit side provided the speed, as expected, but the ComicTank side added something unexpected: visual flair. As he ran, afterimages trailed behind him in comic-panel style, each one frozen in a dramatic pose. It was like he was leaving a manga in his wake, his movement creating narrative.
He tested the strength next, punching one of the arena's reinforced training dummies. The Tank essence provided the power, but the Comic essence added narrative weight—the impact was accompanied by a visual "WHAM" effect that appeared in the air like a sound effect from a printed page, and the dummy didn't just break. It shattered dramatically, pieces flying outward in aesthetically pleasing arcs.
"Okay," Build said, breathing hard with excitement rather than exertion. "Okay. This is incredible. The hybrid bottle works. It creates a new Best Match that combines the properties of both parent essences. And the result is stronger than either individual component."
He detransformed, the armor dissolving back into the Driver, and immediately began planning his next experiment.
The RabbitNin bottle took three hours to create.
It was more difficult than ComicTank had been. Rabbit and Ninja were both organic essences, which meant they existed on the same conceptual plane—their frequencies were similar, their wavelengths overlapping in ways that made them resistant to combination. The resonance chamber had to be recalibrated multiple times, the energy inputs adjusted and readjusted, before the two essences finally agreed to merge.
But when they did, the result was spectacular.
RabbitNin was a deep crimson color, darker than the pure red of Rabbit but lighter than the black of Ninja. The essence inside moved with fluid grace, sometimes visible and sometimes seeming to disappear entirely as light passed through it. Build could feel the bottle humming with potential energy—speed and stealth combined, the ability to move faster than the eye could track while simultaneously being invisible to conventional detection.
He tested it immediately, combining RabbitNin with Tank in the standard organic/inorganic configuration.
RABBITNIN! TANK!
SHINOBI NO BULLET! RABBITTANK!
Wait, that wasn't right. The announcement should have been different—should have reflected the new combination. Build looked at the Driver in confusion for a moment before realizing what had happened.
The hybrid bottle was registering as a variant of its parent essences. RabbitNin was still "Rabbit" to the Driver, just... more. The transformation sequence was using the standard RabbitTank announcement because the fundamental components were the same—speed paired with power—even if the specific expression was different.
The armor that formed around him confirmed this theory.
It was RabbitTank, recognizably—the divided red and blue, the spring-loaded leg on one side and the tank treads on the other. But the red side was different. Ninja elements had been incorporated into the design: throwing stars embedded in the shoulder armor, a face mask that extended from the helmet to cover the lower jaw, gauntlets designed for both punching and precise blade work.
And the speed. Oh God, the speed.
Build moved, and the world seemed to slow down around him. The Rabbit essence had always provided enhanced speed, but the Ninja essence added something new: efficiency. Every movement was optimized, every gesture flowing into the next with the grace of a trained assassin. He wasn't just fast. He was surgically fast, precision fast, assassination fast.
He could feel himself flickering in and out of visibility as he moved, the Ninja essence's stealth capabilities activating instinctively when he exceeded certain speed thresholds. To an outside observer, he would appear as a red blur that occasionally vanished entirely, only to reappear somewhere else in the arena without any apparent transition.
"This is broken," Build announced to the empty arena. "This is absolutely broken. I love it so much."
He detransformed and got back to work.
The next several hours were a blur of experimentation.
Build created bottle after bottle, exploring the possibilities of hybrid essences with the enthusiasm of a child in a candy store. Each new combination revealed new properties, new synergies, new potential for overpowered nonsense that made him cackle with glee.
GorillaDiamond was a strength-focused hybrid that combined Gorilla's raw power with Diamond's hardness. The resulting bottle was pale blue with crystalline structures visible inside, and when used in a transformation, it produced armor that could punch through almost anything while being effectively invulnerable to physical damage.
HawkGatling became a single hybrid bottle that combined aerial mobility with sustained firepower. The flight capabilities were somewhat reduced compared to pure Hawk, but the Gatling component was always available—Build could fly and shoot simultaneously, becoming a one-man aerial assault platform.
PhoenixDragon merged two legendary creatures into something that felt almost mythological. The bottle burned with internal fire, and the armor it produced was ornate and powerful, capable of generating both flames and draconic energy attacks while being completely immune to heat and fire.
OctopusLock combined flexibility with impenetrability, creating a defensive form that could adapt its shape while maintaining absolute structural integrity. Build tested it by having the arena's weapon systems fire on him repeatedly; the armor simply flowed around the attacks, redirecting force and absorbing impacts without any damage.
Each hybrid bottle was stronger than its component parts. Each new Best Match was more overpowered than the last. And Build was just getting started.
Because he had noticed something during the creation process. Something interesting. Something that made his scientist's heart sing with anticipation.
The hybrid bottles could be combined with each other.
"This is probably a terrible idea," Build announced to the empty lab.
He had returned from the testing arena with a dozen new bottles and a head full of increasingly ambitious plans. The workbench was covered in notes and diagrams and theoretical formulas that would have given any actual physicist a migraine.
In front of him sat two hybrid bottles: RabbitNin and ComicTank.
RabbitNin contained the essences of Rabbit and Ninja, merged into a single super-organic component. ComicTank contained the essences of Comic and Tank, merged into a single super-inorganic component.
What would happen if he merged the merges?
"If this works," Build mused aloud, "I'll have created a bottle containing four essences. Rabbit, Ninja, Comic, and Tank. Speed, stealth, narrative weight, and power. All in one container."
He adjusted the resonance chamber's settings, pushing the energy input to levels that made the sensors flash warning signs.
"And if it doesn't work, I'll probably explode. Which would be unfortunate."
He paused, considering.
"But I'll never know unless I try. That's the law of science. That's the law of Build."
He placed both hybrid bottles in the chamber and initiated the sequence.
The reaction was immediate and violent. The chamber shook. The lights flickered. Energy crackled along the walls in patterns that looked distinctly unhealthy. Build had approximately three seconds to wonder if he had made a terrible mistake before the chamber exploded outward in a burst of multicolored light.
When his vision cleared, the chamber was a smoking ruin.
But sitting in the center of the wreckage, glowing with internal radiance, was a new bottle.
It was larger than any bottle Build had created before—nearly three times the size of a standard FullBottle, with a shape that was more like a cylinder than the traditional bottle configuration. Its color was impossible to describe: it seemed to shift between red, black, blue, and purple depending on the angle of viewing, never settling on a single shade. The essence inside moved with aggressive purpose, swirling and churning like a contained storm.
Build picked it up with trembling hands.
The power inside was immense. He could feel it pressing against his consciousness, testing his worthiness, demanding to be used. It was more than a FullBottle. It was more than a hybrid. It was something new—a compound essence that contained multitudes.
"RabbitNinComicTank," he whispered. "A Quad Bottle. Four essences in one."
He needed to test it. He needed to test it right now.
But the resonance chamber was destroyed, and the testing arena was probably not equipped to handle whatever this transformation would produce.
Build grinned.
"Good thing I know somewhere that is."
The Watchtower was the Justice League's primary base of operations—a massive space station orbiting Earth, equipped with technology from a dozen different alien civilizations and the combined resources of the planet's greatest heroes. It had observation decks and meeting rooms and quarters for all active League members and, most importantly for Build's purposes, a training room designed to withstand conflicts between Superman-level threats.
Getting access to the Watchtower had required calling in the favor of provisional membership, but Batman had eventually agreed to let Build use the facility for "extreme capability testing." The Dark Knight had also insisted on observing, which Build had accepted because arguing with Batman was pointless and also because he kind of wanted someone to witness what was about to happen.
The training room was a vast spherical chamber, its walls lined with adaptive armor that could reconfigure to absorb various types of damage. Holographic projectors could simulate any environment. Gravity could be adjusted. The room had been used for training sessions between Superman and Wonder Woman, for power testing of newly-discovered metahumans, and for the occasional interdimensional incursion containment.
It was probably adequate for a Quad Bottle test.
Probably.
Build stood in the center of the chamber, the massive bottle in his hand, the Build Driver humming with anticipation on his waist.
Batman watched from an observation booth high above, his expression unreadable behind the cowl. Wonder Woman was with him—she had heard about the experiment and insisted on observing, her warrior's instincts interested in seeing what this new form could do.
"Recording experiment forty-seven," Build announced, his voice carrying through the chamber's audio systems. "Attempting first transformation using Quad Bottle: RabbitNinComicTank. Combining with... actually, I don't know what to combine it with. The bottle already contains four essences. Using another bottle might cause some kind of essence overflow."
He considered the problem.
"Let's try using it alone. The Driver has two slots, but maybe a Quad Bottle can occupy both simultaneously."
He inserted the RabbitNinComicTank bottle into the right slot. The Driver made a sound it had never made before—a deep harmonic that seemed to resonate with reality itself—and then displayed a new announcement:
RABBINCOMITANK!
The portmanteau was awkward, but the energy was undeniable. The Driver recognized the Quad Bottle as a complete combination in itself, not requiring a partner to achieve Best Match status.
Build grabbed the Vortex Lever.
"Are you ready?" he asked the universe.
He cranked the lever.
ULTIMATE MATCH! RABBINCOMITANK! YEAH!
The "Yeah" was new.
The transformation was overwhelming.
Energy exploded outward from the Driver in concentric waves, each one carrying a different aspect of the four essences. Red for Rabbit. Black for Ninja. Blue for Tank. Purple for Comic. The colors intertwined and separated and merged again, creating patterns that looked like they had been designed by a god with a very advanced graphics program.
The armor that formed around Build was unlike anything he had worn before.
It was larger than normal—adding several inches to his height and significant bulk to his frame. The base color was a deep, shifting indigo that sometimes flared to red or black or blue depending on the light. Comic-book style panel lines divided the armor into dramatic sections, each one featuring stylized renderings of the four essence symbols. Speed lines trailed from every edge even when he stood still. Throwing stars were embedded throughout the design like decorative elements. Tank components—treads and barrels and armor plates—were integrated seamlessly into the overall aesthetic.
The helmet was a masterpiece. Four eyes rather than the standard two—each one representing a different essence, each one capable of independent tracking. The face mask from the Ninja essence covered the lower portion, giving the helmet a mysterious quality. Comic-style dramatic shading made the entire head look like it belonged on a manga cover.
And the power.
The power was indescribable.
Build took a single step forward, and the floor cracked beneath his foot from the sheer force of the movement. He raised his hand, and energy crackled between his fingers—red and black and blue and purple, all four essences responding to his will simultaneously.
"This is insane," he breathed, his voice distorted by the helmet into something deep and resonant. "This is absolutely insane. I can feel everything. The speed of Rabbit. The stealth of Ninja. The narrative weight of Comic. The power of Tank. All of it, all at once, perfectly balanced."
He looked up at the observation booth.
"I think I might be one of the strongest beings on the planet right now."
Batman's expression didn't change—it never did—but there was something in his posture that suggested concern. Wonder Woman, by contrast, looked intrigued.
"Demonstrate," she called down.
Build grinned behind his helmet.
"With pleasure."
The demonstration lasted for approximately fifteen minutes and resulted in the complete destruction of the training room.
Build moved through the space like a force of nature, testing every capability the RabbitNinComicTank form provided. He ran at speeds that exceeded anything the Rabbit essence alone had offered—fast enough that the room's tracking systems lost him entirely for several seconds at a time. He punched the reinforced walls with Tank-enhanced strength that was somehow even greater than TankTank form would have provided, cratering the adaptive armor and forcing the room's repair systems into overdrive.
He demonstrated the Ninja stealth by completely vanishing from all sensors—visual, thermal, electromagnetic, even the mystical detection systems that Wonder Woman had contributed to the Watchtower's design. Batman could not find him. The room's AI could not find him. He simply did not exist to any form of detection until he chose to reappear.
And the Comic essence added narrative weight to everything he did. When he punched, visual sound effects appeared in the air—"WHAM" and "KRAKOOM" and "ULTIMATE IMPACT"—rendered in dramatic fonts that floated for several seconds before fading. When he moved, afterimages followed in comic-panel style, creating a visual record of his actions that looked like pages from a manga. When he spoke, word bubbles sometimes materialized, lending additional emphasis to his declarations.
By the time he was finished, the training room looked like a warzone.
"Okay," Build said, breathing hard despite the armor's life support systems. "Okay. That was... a lot. That was a lot of power."
"You destroyed a room designed to contain Superman-level conflicts," Batman observed, his voice carrying a note of something that might have been concern or might have been respect. Possibly both.
"Yeah. I might have gotten a little carried away."
He detransformed, the RabbitNinComicTank armor dissolving back into the Driver. The Quad Bottle ejected automatically, and Build caught it with reflexes that were still enhanced from the transformation.
"The good news is that the Quad Bottle works. The hybrid-of-hybrids concept is valid. I can create compound essences that combine multiple bottles into single, more powerful combinations."
"And the bad news?" Wonder Woman asked.
Build looked at the devastated training room.
"I probably shouldn't use this form unless I'm fighting something that can actually threaten me. Which, at this point, might be a pretty short list."
The experiments continued over the following days.
Build created more hybrid bottles, exploring different combinations and documenting the results with scientific rigor. He discovered that not all essences were compatible with merging—some combinations produced unstable bottles that degraded over time, while others simply refused to merge no matter how much energy he pumped into the resonance chamber.
But the successful merges were spectacular.
SameDragonFire combined the same essence (a mysterious element that seemed to be pure identity), Dragon, and Phoenix's fire aspect into a bottle that produced a form of incredible mystical power. The armor was serpentine and flame-wreathed, capable of generating fire that burned on a conceptual level rather than a physical one.
UnicornSoujiki combined the unicorn essence with the vacuum cleaner essence—Build still wasn't sure why he had a vacuum cleaner bottle, but he wasn't going to question the Driver's mysterious ways—and produced a form that could purify corruption and absorb negative energy. It was probably the weirdest combination he had created, but also one of the most situationally useful.
KaizokuRessya combined pirate and train essences for no reason other than Build thought it would be cool. The result was armor that could travel along any surface as though it were a track while also generating holographic pirate-themed weapons. It made no logical sense whatsoever. Build loved it.
But the experiments that truly changed everything were the Hazard experiments.
The Hazard Trigger was a dangerous piece of technology.
In the original show, the Hazard Trigger had been designed to increase Build's power at the cost of control. It pushed the user's aggression to dangerous levels, overwhelmed their rational mind with combat instincts, and in extreme cases could cause the user to attack allies as well as enemies. It was a power-up with severe drawbacks, a devil's bargain that offered strength in exchange for sanity.
Build had been hesitant to experiment with the Hazard system for exactly this reason. He wasn't Sento Kiryu. He didn't have the genius physicist's mental discipline or the years of experience controlling his emotions in combat. Using the Hazard Trigger carelessly could result in him hurting someone—or worse.
But the potential was too great to ignore entirely.
The Hazard Trigger, when combined with certain FullBottles, produced some of Build's most powerful forms. Hazard RabbitTank had been devastating. Hazard CrossZ had been terrifying. And according to the show's lore, the Hazard system could theoretically be applied to any form, multiplying its power exponentially.
What would happen if Build applied the Hazard system to his hybrid bottles?
What would happen if he created a Hazard Quad Bottle?
What would happen if he created Hazard Genius?
The thoughts haunted him for days before he finally gave in to curiosity and began planning the experiments.
"You want to do what?"
Batman's voice was flat with disapproval. They were in the Watchtower's briefing room, Build having called a meeting specifically to discuss his planned experiments with the Hazard system.
"I want to create Hazard-enhanced hybrid bottles," Build explained, pointing to diagrams on the holographic display. "The Hazard Trigger is essentially an amplifier—it increases the output of any form it's applied to by a significant factor. My hypothesis is that applying Hazard enhancement to hybrid bottles will produce even greater increases, because the compound essences already contain more power than standard bottles."
"And the drawbacks?" Wonder Woman asked.
"The Hazard system's primary drawback is psychological. It increases aggression, reduces rational thought, and in extreme cases can cause complete loss of control. But I believe these effects are related to the amplification of the user's combat instincts—the system pushes you to fight harder by suppressing the parts of your brain that would normally limit aggression."
He pulled up more diagrams.
"My theory is that the Hazard drawbacks can be mitigated through careful calibration. If I can adjust the amplification parameters to target physical capabilities rather than psychological ones, I might be able to retain control while still benefiting from the increased power."
"That's a lot of 'might' and 'theory,'" Batman observed. "What happens if you're wrong?"
Build was silent for a moment.
"If I'm wrong, I could lose control during transformation. Attack allies. Cause significant collateral damage. Potentially hurt or kill innocent people."
The room was quiet.
"But," Build continued, "if I'm right, I'll have access to power levels that could make a difference against threats that even the Justice League struggles with. Darkseid. The Anti-Monitor. Imperiex. Beings that exist on cosmic scales, with power that dwarfs anything Earth's heroes have faced before."
He looked around the table at the assembled League members.
"I know this world. I know what's coming. There are threats out there that will require everything we have and more. If I can develop the Hazard system safely, it could be the difference between victory and extinction."
Wonder Woman spoke first. "I believe him. His knowledge of our world has proven accurate so far. If he says there are threats that require this level of power, we should take that seriously."
Superman nodded slowly. "I don't like the risks, but I understand the necessity. Is there any way we can minimize the danger?"
"I have some ideas," Cyborg offered. "If I can interface with the Build Driver, I might be able to create failsafes—override systems that can trigger detransformation if Build's psychological state becomes unstable."
"I can prepare containment," J'onn added. "Mental barriers that might help resist the Hazard system's psychological effects."
Build felt a warmth spreading through his chest. These people were willing to help him. Despite the risks, despite the dangers, they were treating him as an ally worth supporting.
"Thank you," he said. "All of you. I promise I'll be careful."
Batman's expression remained skeptical, but he didn't object.
"Begin with small-scale tests," the Dark Knight said finally. "Standard Hazard forms before hybrid applications. Document everything. And if there's any sign of instability—any sign at all—we shut it down immediately."
Build nodded.
"Understood."
The first Hazard experiment was simple: standard Hazard RabbitTank.
Build had the original Hazard Trigger—it had appeared in his bottle carrier one morning, as the Driver's mysterious supply system continued to provide whatever he needed—and used it in the traditional manner, slotting it into the Driver alongside the Rabbit and Tank bottles.
RABBIT! TANK! HAZARD ON!
UNCONTROLLABLE SWITCH! BLACK HAZARD! YEAHHH!
The transformation was violent. Energy exploded outward in waves of black and red and blue, the mathematical formulae rendered in harsh angles and aggressive patterns. The armor that formed was RabbitTank, but darker—the colors shifted toward black, the design elements sharper and more aggressive.
And Build felt the psychological effects immediately.
Rage bubbled up from somewhere deep inside him—an anger that had no specific target, that simply demanded outlet. His vision narrowed. His thoughts simplified. The complex calculations that usually ran through his mind during combat collapsed into a single imperative: FIGHT.
"Control," he muttered, forcing the word through gritted teeth. "Maintain control."
Cyborg's failsafe systems beeped in his helmet, monitoring his psychological state. J'onn's mental barriers pushed back against the rage, providing a buffer between the Hazard impulses and his rational mind.
It helped. It wasn't perfect, but it helped.
Build took several deep breaths, focusing on the techniques he had researched for emotional regulation. The rage was still there, burning in his chest, but it was manageable. He could think. He could plan. He could choose his actions rather than being driven by pure instinct.
"Status?" Batman's voice came through the communication system.
"Manageable," Build reported. "The psychological effects are significant, but J'onn's barriers and Cyborg's monitoring are helping. I can feel the aggression, but I can also feel myself resisting it."
"Power levels?"
Build looked at his hands, feeling the energy coursing through the black armor.
"Substantially increased. The Hazard system is amplifying everything—strength, speed, durability. I'd estimate this form is approximately twice as powerful as standard RabbitTank."
He tested the form's capabilities, moving through training sequences while the League observed. The power was undeniable—he was faster, stronger, more durable than he had ever been in a standard form. But the psychological cost was equally undeniable. Every moment in Hazard form was a battle against his own instincts, a constant struggle to remain in control.
After thirty minutes, he detransformed.
"Okay," he said, breathing hard. "Okay. That was intense. But I maintained control throughout. The failsafes work. The mental barriers work. It's difficult, but it's possible."
Batman nodded slowly. "Proceed to the next phase. But carefully."
Hazard RabbitRabbit was next.
In the original show, RabbitRabbit form had been Build's speed-focused upgrade—using two Rabbit bottles simultaneously to double down on agility and quickness. Adding the Hazard system to this form produced something that moved so fast it was effectively teleporting.
Build tested it briefly, disappearing from one end of the training room and reappearing at the other in what the sensors reported as zero elapsed time. The psychological effects were similar to Hazard RabbitTank—significant aggression, reduced rational thought—but the speed somehow made it easier to control. He could outrun his own rage, moving so fast that the Hazard impulses couldn't keep up.
"Interesting," he mused after detransforming. "The psychological effects seem to have a tempo—a speed at which they operate. If I can move faster than that speed, I can essentially outpace my own instabilities."
"That's a dangerous strategy," J'onn observed. "What happens when you stop moving?"
"Good point. I'll need to develop better containment for the impulses. But for now, this form is viable for combat use."
Hazard TankTank was the opposite approach—doubled power instead of doubled speed.
The form was massive, the black armor bulky and imposing, covered in tank treads and gun barrels and armored plating. Build felt like he was piloting a walking fortress rather than wearing a suit. The strength was unbelievable—he punched a wall and his fist went completely through, emerging on the other side of the room.
The psychological effects were also more intense. The rage burned hotter, demanded more strongly, pushed harder against his rational mind. Build found himself breathing in short, aggressive bursts, his hands clenching and unclenching with the urge to destroy something.
"Control," he growled, forcing himself to stand still. "Maintain control."
It took longer this time. The Hazard impulses were stronger, the mental barriers straining against the onslaught of aggression. But eventually, he found equilibrium—a razor's edge between power and madness.
"This form is dangerous," he reported. "The psychological effects are significantly stronger than the speed-focused versions. I can maintain control, but just barely."
"Noted," Batman said. "Continue testing, but be prepared to abort if necessary."
The breakthrough came with Hazard RabbitNin.
The hybrid bottle already contained merged essences, which meant the Hazard system was amplifying a combination rather than a single element. Build wasn't sure what to expect—would the psychological effects be doubled because there were two organic essences? Would they cancel out? Would something entirely new happen?
He activated the transformation.
RABBITNIN! HAZARD ON!
SHINOBI UNCONTROLLABLE SWITCH! BLACK HAZARD! YEAHHH!
The armor that formed was breathtaking. Black and deep crimson, the colors of shadow and blood, with throwing stars embedded throughout and a face mask that seemed to absorb light. Speed lines trailed from every surface, but they were dark rather than bright—streams of shadow rather than illumination.
And the psychological effects were... different.
The rage was there, as expected. But layered over it was something else—something cold and calculating that tempered the heat of aggression with the precision of a trained killer. The Rabbit essence wanted to fight. The Ninja essence wanted to win. The combination created not mindless fury, but directed fury—anger with a purpose.
"This is remarkable," Build said, his voice coming out calm and controlled despite the Hazard system's activation. "The hybrid essence is changing the psychological profile. The aggression is still present, but it's being channeled rather than overwhelming me."
"Can you explain?" Superman asked.
"The Ninja essence includes mental discipline as part of its concept. When the Hazard system amplified the hybrid, it amplified that discipline along with everything else. I'm experiencing rage, but I'm also experiencing the tools to control that rage."
He moved through combat forms, his body flowing from stance to stance with lethal grace. The speed was incredible—even greater than Hazard RabbitRabbit—but the precision was what made it terrifying. Every movement was optimized. Every strike was perfect. He wasn't just fast; he was surgically, assassinatorially fast.
"This is it," Build breathed. "This is the key. Hybrid bottles with disciplinary essences can counteract the Hazard system's psychological effects. I can have the power without losing myself."
He detransformed, his mind already racing with possibilities.
"I need to create more hybrids with control-focused essences. Ninja. Lock. Diamond. Anything that implies mental stability or discipline. If I merge those with aggressive essences before applying Hazard, the results should be controllable."
The creation of Hazard Genius took three days.
Genius Form was the pinnacle of Build's power in the original show—a form that used all sixty FullBottles simultaneously, granting access to every ability Build had ever demonstrated. The suit was covered in the periodic table of elements, a visual representation of mastering all of science.
Build didn't have sixty FullBottles. He had approximately thirty, plus the hybrids he had created. But the principle was the same: combine as many essences as possible into a single transformation, creating a form that contained multitudes.
He started by creating a Genius Bottle—a massive container that could hold multiple merged essences simultaneously. The resonance chamber had to be rebuilt three times to accommodate the necessary energy levels, and the final product was more of a cylinder than a bottle, nearly a foot long and covered in scientific notation.
Into this container, Build merged the essences of every hybrid bottle he had created.
RabbitNin went in first, contributing speed and stealth and mental discipline. ComicTank followed, adding power and narrative weight and durability. GorillaDiamond. HawkGatling. PhoenixDragon. OctopusLock. SameDragonFire. Every successful hybrid, every compound essence, every piece of the puzzle.
The merging process was violent. The resonance chamber exploded twice, requiring complete reconstruction. The energy levels exceeded anything Build had worked with before, causing brownouts throughout the Watchtower facility. At one point, reality seemed to flicker around the chamber, the fabric of space-time struggling to contain the conceptual weight being forged within.
But when it was done, Build held in his hands something that felt like holding a universe.
The Genius Bottle was beautiful. Its color was impossible—not shifting between hues like the Quad Bottle, but containing all hues simultaneously, a white-that-was-all-colors radiating from within. The essence inside moved with purpose, a contained cosmos of potential.
"Now," Build said, pulling out the Hazard Trigger, "for the dangerous part."
He modified the Hazard Trigger to interface with the Genius Bottle. The work was delicate—the Hazard system had never been designed for this level of power, and forcing the two technologies together required creative engineering and a fair amount of prayer.
When the modification was complete, Build had a single, massive bottle that contained Hazard-enhanced Genius-level power.
He called it the Hazard Genius Bottle.
It was probably the most dangerous object he had ever created.
"You understand why I'm concerned," Batman said.
They were in the Watchtower's briefing room again, the League assembled to witness—or potentially contain—Build's attempt to use the Hazard Genius Bottle. The chamber had been reinforced with additional Nth metal plating. J'onn had prepared stronger mental barriers. Cyborg had installed failsafes with failsafes with failsafes.
Everyone was nervous.
"I understand," Build said. "But this needs to be tested. If I'm going to use this power in actual combat, I need to know what it does. I need to know if I can control it."
"And if you can't?"
Build looked at the assembled heroes—the most powerful beings on the planet, gathered to observe his experiment.
"Then you stop me. By whatever means necessary."
The room was silent.
"Let's begin," Wonder Woman said finally.
Build stood in the center of the reinforced training chamber, the Hazard Genius Bottle in his hand.
The bottle hummed with power, vibrating slightly against his palm. Inside, he could see the essence moving—a swirl of all colors, all concepts, all possibilities compressed into a single container.
"Recording final experiment," he announced. "Attempting first transformation using Hazard Genius Bottle. Predicted outcome: unknown. Power level: unknown. Psychological effects: unknown. Basically, I have no idea what's going to happen."
He paused.
"But that's what experimentation is all about, right? Discovering the unknown. Pushing the boundaries. Going where no one has gone before."
He inserted the Hazard Genius Bottle into the Build Driver.
The Driver made a sound it had never made before—not an announcement, but something more like a song. A harmony of all the essence-voices that had ever spoken through the device, merged into a single chord of absolute power.
Build grabbed the Vortex Lever.
"The laws of victory have been decided," he said. "Now let's find out what those laws are."
He cranked the lever.
HAZARD GENIUS! COMPLETE CHAOS HARMONY! YEAH! YEAHHH! YEAHHHHHH!
The transformation was not an explosion.
It was an implosion.
Energy rushed inward rather than outward, collapsing around Build like a star forming from cosmic dust. The mathematical formulae that normally swirled through the air during transformation instead crystallized, becoming solid structures of pure equation that orbited his body like electrons around a nucleus.
The armor formed from the inside out—first the undersuit, then the primary armor, then layer after layer of additional components. Each layer represented a different essence, a different capability, a different aspect of the compound Genius form. Rabbit speed. Ninja stealth. Tank power. Diamond hardness. Dragon fire. Phoenix regeneration. Comic narrative. All of it, all at once, stacking and combining and reinforcing each other.
The final layer was the Hazard enhancement—black energy crackling across the entire surface, amplifying everything by orders of magnitude.
When the transformation completed, Build stood in armor that looked like it had been designed by a god.
The suit was primarily white—the white of all colors combined—with black Hazard lines tracing patterns across every surface. The periodic table covered the chest and back, but it was enhanced, extended, including elements that didn't exist in normal reality. Each element symbol glowed with a different color, representing a different essence, a different capability.
The helmet featured not four eyes but six—compound lenses arranged in a hexagonal pattern, each one capable of seeing reality on a different spectrum. Antennae and horns and sensor arrays extended from the crown, giving it a regal, almost divine appearance.
And the power.
Build had felt powerful before. The RabbitNinComicTank form had been overwhelming. The various Hazard forms had been intense.
This was beyond all of that.
He could feel the speed of Rabbit, amplified a thousandfold by the Hazard enhancement. He could feel the strength of Tank, multiplied to levels that defied measurement. He could feel the fire of Phoenix and Dragon, burning with conceptual heat that could consume ideas. He could feel the stealth of Ninja, the narrative weight of Comic, the flexibility of Octopus, the precision of Lock.
He could feel everything, all at once, perfectly balanced despite the chaos.
And the psychological effects...
They were there. He could feel the rage, the aggression, the impulse to destroy. The Hazard system was pushing at his mind, demanding violence, demanding action.
But layered over that was discipline. Control. The accumulated mental stability of every essence that included such qualities, amplified just as much as the aggression. Rage and calm. Violence and precision. Destruction and creation.
Perfect balance.
"Status?" Batman's voice came through the communication system, tense with concern.
Build took a deep breath—feeling air cycle through lungs that were somehow enhanced, processing the oxygen more efficiently than any organic system should allow.
"I am in complete control," he said, and his voice was different. Deeper. More resonant. Like the voice of a deity deigning to speak to mortals. "The Hazard Genius form is... it's everything I hoped for. Everything I imagined. Everything I was afraid of."
"Power level?"
Build looked at his hands, seeing the energy crackling between his fingers. He thought about the various threats he knew existed in this universe—the cosmic beings, the universal forces, the gods and monsters and reality-warpers.
"High," he said. "Very, very high. I'm not sure exactly where I rank, but it's up there. Top tier. Maybe higher than top tier."
There was a moment of silence.
"Demonstrate," Wonder Woman requested.
Build smiled behind his helmet.
"With pleasure."
The demonstration lasted approximately two minutes.
That was how long it took for Build to completely overload every sensor in the Watchtower, destroy the reinforced training chamber beyond any possibility of repair, and accidentally crack three of the space station's structural supports before getting his power under control.
He punched with the force of a small nuclear detonation. He moved so fast that the Watchtower's AI couldn't track him and briefly reported that he had ceased to exist. He generated fire that burned through the adaptive armor plating like it wasn't there. He created holographic copies of himself that each seemed to have independent intelligence.
By the time he detransformed, the training chamber was less of a chamber and more of an open wound in the side of the Watchtower, hastily sealed by emergency forcefields to prevent atmosphere loss.
"Okay," Build said, breathing hard despite the power rush. "Okay. That was... a lot."
"You broke my space station," Batman observed.
"I'll help fix it."
"You broke my space station."
"I said I'll help fix it! I'm a scientist! I can do repairs!"
Batman's expression somehow became even more disapproving, which shouldn't have been physically possible.
"Just... be more careful next time," Superman said, ever the diplomat. "And maybe we should test the really powerful forms somewhere that isn't our primary base of operations."
"Moon?" Build suggested.
"Moon," Superman agreed.
Later that night, after the repairs had begun and the League had dispersed to their various responsibilities, Build stood in the observation deck looking out at Earth.
The Hazard Genius Bottle sat in his hand, dormant now, its incredible power waiting to be called upon again. Around his waist, the Build Driver hummed with satisfaction, pleased with the experiments that had expanded its capabilities.
He had done it.
He had created hybrid bottles. Quad bottles. Compound Genius-level bottles. Hazard-enhanced forms that could stand against cosmic-level threats. He had pushed the boundaries of what the Build Driver could do and discovered that those boundaries were further away than anyone had imagined.
And he was just getting started.
There were more combinations to try. More essences to merge. More power levels to achieve. The DC Universe was full of threats that would require everything he had, and now he knew that "everything he had" was considerably more than he had initially believed.
Fusion forms.
The thought kept returning to him, a tantalizing possibility that he hadn't yet explored.
In the Kamen Rider franchise, fusion forms involved combining with other Riders—merging two warriors into a single, more powerful entity. Build had fused with Zi-O to fight Oma Zi-O. Cross-Z had fused with Build in various combinations throughout their partnership.
Could he fuse with someone from this universe?
What would happen if the Build Driver interfaced with a Kryptonian? With an Amazonian? With a Speed Force conduit or a Green Lantern ring-bearer?
The possibilities were endless.
And Build was determined to explore every single one of them.
"The laws of victory have been decided," he said to the Earth below, to the stars above, to the universe that had given him this incredible gift. "And those laws say that I'm going to keep getting stronger until nothing can stop me."
He smiled.
"Now... where do I start?"
To Be Continued...