The forest’s towering canopy and deep shadows were almost welcoming… in a hostile kind of way. Kaizo found a thick old tree near a small stream and got to work.
By sundown, he had a functional treehouse: a sturdy floor, makeshift railing, and just enough shelter to keep rain off his head. Inside, he set up his travel bed, laptop, and supplies. It wasn’t much, but it would be home base for the next week.
Kaizo (dropping into the bed): “Alright. Tomorrow, the real fun starts.”
Night Study
That night, he sat cross-legged under a lantern, flipping through anatomy charts and scribbling notes. Having already passed med school, he was attempting to apply what he learned with his newfound abilities. Based on how he saw the outline of his body from the Infinity Realm, he traced muscle groups, vein pathways, and nerve lines, memorizing exactly what parts of his body would take the most strain.
His training goals were clear:
Get his body back to prime condition—or better.
Understand his linked DNA abilities with Infinity.
Explore the origins of this so-called “jungle.”
The DNA Set System
To keep his DNA switching consistent, Kaizo devised a set system: three animal DNAs per set, each focused on one utility.
Kaizo: “You think three is a good enough number?”
Infinity: “Probably. Unless you wanna spontaneously combust.”
Kaizo: “…Thanks for the visual.”
For his sets, he decided to focus on factors that would be the focus of a fight. After doing his research, these are the sets he settled on so far:
Physical Sets:
Speed – Cheetah / Peregrine Falcon / Swordfish
Strength – Gorilla / Dung Beetle / Grizzly Bear
Agility – Tree Frog / Dragonfly / Panther
Reaction – Mantis Shrimp / Hummingbird / Housefly
Vertical – Kangaroo / Grasshopper / Mountain Goat
Sensory Sets:
Sight – Eagle / Chameleon / Dragonfly
Scent – Bloodhound / Elephant / Bear
Hearing – Barn Owl / Bat / Greater Wax Moth
Taste – Catfish / Cow / Rabbit (Infinity’s idea)
Touch – Spider / Platypus / Star-nosed Mole
Battle Sense / Awareness – Echolocation (Bat) / Radiation Detection (Snake) / Spatial Awareness (Chimpanzee)
Technique Set: Gecko Wall-Crawling (only one ability so far)
Limits Discovered
On the second day, Kaizo tried activating Speed, Strength, and Agility together.
That ended up going horribly.
A sharp pain ripped through his stomach, and he collapsed, coughing blood. Infinity dove into his body to stabilize his DNA.
Infinity: “Idiot! Your body can’t handle that much at once!”
Kaizo (gasping): “Yeah… noted…”
After some painful tests, they set some limits:
Option 1: 1/3rd of each slot of a set with 3 sets activated at a time
Ex: Speed Set (Cheetah), Strength Set (Gorilla), Agility Set (Panther)
Option 2: 3 full slots of one set at a time
Ex: Speed Set; Max Form (Cheetah X Peregrine Falcon X Swordfish)
They also began to focus on strengthening the body to handle high-intensity sets, especially Strength. One interesting thing Infinity noticed and mentioned to Kaizo is that his own physical abilities were taken into account while he had a set active, meaning that the full potential of a set could be increased with continual training.
Basically, if Kaizo keeps improving on his own strength, when the Strength Set is active, it multiplies the chosen animal's ability by the user’s current strength level.
Ex: Kaizo’s Maximum Lift: 110 lbs X Strength Set 1/3rd (Gorilla) = 110 lbs × 4,000 lbs = 440,000 lbs2
If Kaizo can now lift 125lbs, the equation changes to
Kaizo’s Maximum Lift: 125 lbs X Strength Set 1/3rd (Gorilla) = 110 lbs × 4,000 lbs
Kaizo spent the rest of the week pushing himself.
Sprint drills through the underbrush/ open plains for speed.
Log lifts and stone carries for building his strength.
Flexibility and balance exercises using tree branches for increasing his agility.
Infinity joined in, effortlessly switching through sets without any drawbacks—just to rub it in.
The sensory sets caused less strain, so he was able to use them majority of the time and as a result, Kaizo’s awareness improved drastically—every sound was sharper, every scent was clearer, every movement in the trees more noticeable. His growth was due especially because of the method he was combining them with, though we would learn more about it later.
Kaizo: “By the end of this week, we’re going to be dangerous.”
The tale has been taken without authorization; if you see it on Amazon, report the incident.
Infinity: “We already are.”
Kaizo (chuckling): “That’s true…”
Sparring in the Jungle of Time
Kaizo didn’t just train by himself—he fought a lot.
The Jungle of Time was crawling with PrimeBeast species, each more unpredictable than the last. A lot of the time, Kaizo would train with a different species, defeat them and discover more about them later. With Infinity’s ability to communicate with him, Kaizo was able to test out his new abilities and some old techniques. He treated them as moving, clawed, dangerous punching bags (well, only the feisty ones).
By the end of the week, his record stood at 68 wins, 3 losses.
Not bad, considering some of those things could snap a tree in half.
Through battle, Kaizo picked up even more techniques and learned just how insane Infinity’s abilities could benefit him. He discovered he could consciously control his own blood vessels and other vitals parts and organs. Also with the fact that he could speed up cellular creation and growth, that gave birth to his newest trick: Regen Protocol—a self-induced healing factor. It did take a lot of focus to do that though.
But he didn’t stop there.
According to his research from the Animal Planet channel, (Yes, Kaizo found a way to watch the stuff we watch) axolotls and geckos could regrow limbs, so he put that ability into a brand-new Healing Set. Combined with the Regen Protocol, his recovery speed became almost instantaneous. Minor injuries? Gone in seconds. Deep cuts? Minutes. That meant longer, harder training sessions without losing momentum/stamina.
On the fourth day, Kaizo was sitting in the shade, munching on some wild fruit. One bite in, he gagged.
Kaizo (grimacing): “Ugh—this one’s rotten.”
Infinity: “Hold on.”
Before Kaizo could spit it out, Infinity altered the flavor compound—and more than that, the fruit’s chemical makeup. What was once rancid was now sweet, crisp, and nutritionally perfect.
Kaizo: “…Wait. You’re telling me you could’ve done this the whole time?”
Infinity just nodded.
Kaizo grinned like a man who’d just unlocked cheat codes.
Kaizo: “I’m gonna be a PrimeBeast myself at this rate.”
From then on, he used this ability to eat anything—rotten fruit, raw meat, weird glowing jungle plants—while making sure it gave his body exactly what it needed. Proteins, carbs, electrolytes, vitamins… all tailor-made on the spot.
By the seventh day, Kaizo was ready to leave. He pulled out his phone and called Yumi.
Kaizo: “Hey, when are we leaving for the tournament?”
Yumi (sleepily): “Kaizo… it’s Saturday. The day after school. We’re nowhere close to Friday.”
Kaizo blinked. What?
Kaizo: “Uh… right. Sorry. Can you just call me on the actual day we’re leaving?”
She agreed and hung up.
Kaizo stood there for a long moment, staring at the trees.
Kaizo (to Infinity): “We’ve been here a week.”
Infinity: “…Apparently not.”
They headed back toward the heart of the jungle, but now Kaizo had a gnawing question lodged in his mind:
What the hell is up with this forest?
Kaizo didn’t waste the extra time the forest seemed to give him. If anything, the anomaly gave him more space to dig into something he’d been meaning to revisit—his father’s art.
Mugen Sentō-ryū (無限戦闘流) — Unlimited Combat Style.
A legendary martial art said to have no true form because it was every form. His father had built it like a vast labyrinth of techniques, weaving together the essence of countless martial arts he had seen from around their world.
(Of course, Kaizo would later find out that the majority of those martial arts were really just based on martial arts from our world.)
It wasn’t just a mishmash—it had paths.
Each path specialized in a distinct approach: fists, kicks, throws, counter-attacks, weapon adaptation, even unconventional body movements that borrowed from animal mimicry.
For example (Luckily for us, Kaizo had determined how most of them look like for us):
Fist Path: Boxing, Karate, Muay Thai, Wing Chun, Russian Fist Fighting
Kick Path: Taekwondo, Savate, Capoeira, Muay Boran
Counter Path: Aiki-jūjutsu, Systema counters, Wing Chun deflections, Filipino Dumog sweeps
And more, each balanced for adaptability and pure efficiency.
Kaizo knew most of the paths well, but one stood above the rest for him—the Counter Path. It was his and his father’s shared favorite, the art of using an opponent’s own momentum to dismantle them.
Now, armed with Zenshin and his DNA sets, Kaizo began evolving Mugen Sentō-ryū beyond anything his father could’ve imagined. He experimented with hybrid moves, like a counter sweep performed with panther-level agility, or a guard break infused with gorilla-tier strength.
Every day, he was carving a new version of the style—one that was still Mugen Sentō-ryū at its core, but now pulsing with the raw adaptability of nature itself.
Kaizo spent 84 full days sharpening his body, mind, and technique in the Jungle of Time—though, to him, it still felt like a week. (Seven days on Earth × the Jungle’s 12× time rate = 84 days of nonstop training. He and Infinity had no idea about this little quirk yet.)
In that time, he developed and mastered a set of techniques that fused Mugen Sentō-ryū with his DNA abilities. One of his proudest creations was something he called Mugensoku (無現速 — Infinite Speed).
The inspiration?
A late-night Animal Planet binge in the treehouse with Infinity, where they learned that a mantis shrimp can throw one of the fastest punches in the natural world—so fast that it boils water in its wake. Kaizo saw potential in the move.
He took the mantis shrimp’s raw speed, injected it into his Technique Set, blended it with professional boxing mechanics, and then ran it through the Fist Path of Mugen Sentō-ryū. The result was a strike so fast it erased the motion between preparation and impact—your brain simply skipped the part where his arm moved.
In practice, Kaizo stepped into his stance, eyes forward. He exhaled a heavy sigh. A split second later, a mountainside exploded into a gaping crater. The rock still echoed from the shockwave.
It was beautiful. It was devastating. It was art. And of course—Infinity had to ruin the moment.
Infinity: “Why did you sigh like that?”
Kaizo: “What?”
Infinity: “Was that necessary?”
Kaizo: “Do you have anything else to do?”
Infinity: “Not particularly.”
In the middle of his training, Kaizo and Infinity decided to explore more of the Jungle of Time. The deeper they went, the more impossible it seemed that this place existed naturally.
They found entire environments scattered like islands across the jungle. A volcano rumbled in the distance, its glow visible even in daylight. A massive ocean stretched out far beyond the treeline. At the very center of the jungle sat a colossal lake, where countless PrimeBeast species gathered to drink. Kaizo often held his spars there; over time, the animals became so accustomed to him that some began watching his battles—almost like a crowd of regular spectators. A few even acknowledged him with subtle bows or low growls of respect.
Beyond the forest lay even stranger regions: a frozen iceberg towering into the clouds, a sweltering desert with golden dunes, vast swamps, colossal mountains, and lush tropical forests.
Kaizo: “What kind of experiment happened for this place to be like this?”
Infinity: “No idea. All I know is the experiments changed my… and their lives forever…”
A pause hung in the air.
Kaizo: “…Does it still hurt thinking about it?”
Infinity (smiling): “Not really, ’cause now I got you!”
Kaizo (grinning): “Can’t say I’m disappointed either.”
Days later, Yumi’s call finally came through and they got ready to depart for the tournament.
Kaizo stood at the edge of the forest, staring back at the wilderness that had been his home for the past “week.” The wind carried the scent of pine, salt, and ash from every environment he had visited.
Infinity: “Are we leaving?”
Kaizo: “Yeah… let’s go.”
With that, they turned toward the path out of the jungle.
