Pressure and Progress

Kai blinked up at the ceiling, the morning sun slicing through the blinds in thin, golden beams. He felt… different. Not just rested — stronger. He sat up slowly, glancing down at his arms. Every fiber of his body hummed like it was coiled steel. His muscles felt dense, his breathing light, and his senses sharp in a way that made the world feel slower.

"…What the hell?" he muttered, swinging his legs off the bed. A flick of thought brought up his system interface, glowing faintly in the air like a projection only he could see.

[Current Power Level: 100,000,000]

He stared at it, unblinking.

"No. No no no no. That… what?"

He hadn't even trained last night. At least, not seriously. And he hadn't hit a new gravity threshold or eaten some super bean or meditated under a waterfall while floating upside-down.

So why…?

His eyes narrowed. "It's the Kaioken."

He stood up and flexed a hand, feeling the strength ripple up through his shoulder and back. The body strain from x4 last night — the constant repetition, the system adapting faster and deeper with every multiplier — it hadn't just made the technique easier.

It had made him stronger. Permanently.

He rubbed his temples and groaned. "Of course my body would treat Kaioken strain like a workout bonus. Stupid broken system."

Still, he couldn't complain. 100 million. That was absurd. Even if he kept his true strength suppressed — and he would — it meant he had breathing room. Against Vegeta's pod? Easy. Against Frieza down the line?

…Well. That was a problem for later.

He showered, got dressed in his usual combat gear, and flew off toward Kami's Lookout.

The breeze felt good. Almost nostalgic now, in a weird way. It reminded him of the early days — barely being able to fly straight, panting after every sprint, trying not to die every time his body "adapted" through near-death experience.

Now? Now the clouds parted when he flew by. The air moved around him like it respected him. Or feared him. Probably both.

When he arrived, the others were already there — Goku, Gohan, Piccolo, Krillin. Even Mr. Popo and Kami stood nearby, watching with that serene-but-secretly-nervous look the latter always wore around unpredictable humans.

"Yo," Kai said, landing with a grin and a lazy salute. "How's everyone feeling after the 'giant monkey destroys the world' incident?"

Goku turned with a grin of his own. "Better. Thanks to you guys — and the senzu bean."

Kai raised a brow. "You sure? That Kaioken technique you pulled looked like it was trying to set your insides on fire."

"Yeah," Goku admitted, rubbing the back of his neck. "Still getting used to it. But it's strong. Strong enough to beat that Vegeta guy, at least."

Piccolo gave Kai a look. "And you. You've gotten stronger. A lot stronger."

Kai shrugged, doing his best to look normal. "I mean, I ate, I slept, I lifted a mountain or two. Good for circulation."

Krillin snorted. "That's terrifying."

Kami stepped forward, his voice calm but firm. "If you're all serious about getting stronger before the next threat arrives… there's something I can offer. But it's not easy."

Gohan blinked. "What is it?"

Kami gestured behind him. "The Hyperbolic Time Chamber. One day in there equals a year outside. But be warned — the gravity is immense, the temperature unstable, and the mental strain… severe."

Kai's eyes practically sparkled. "That sounds like heaven."

Krillin raised a hand. "Can I not go in? I get motion sick just looking at the door."

In the end, it was Goku, Kai, and Gohan who stepped inside — with Piccolo deciding to train Gohan afterward on his own, once the chamber had cycled through.

The door sealed behind them.

White. That was the first thing Kai noticed. The chamber was nothing but endless white — sky, floor, walls — all blending into one infinite horizon. The gravity felt heavier, too. Not crushing, but dense. Like every step mattered.

They walked for a bit, finding a central area with supplies and bedding.

Kai stretched. "This place is basically a stress simulator."

Goku cracked his knuckles. "Let's test how stressful."

They squared off.

Kai made sure to suppress his power, locking it at a solid 50,000. Goku mirrored him, eager grin on his face.

The spar began with fast jabs and swift dodges, each move blurring to the average eye. The air cracked with every blocked strike, their feet carving trails into the polished white floor.

Then Goku flared red.

"Kaioken!"

The red aura snapped to life, pulsing around him with raw, explosive energy.

Kai didn't respond in kind. He weaved through the hits, blocking and dodging, keeping up without using his own Kaioken — or giving away the fact that he'd long since surpassed it.

Goku came in with a high-speed roundhouse. Kai ducked low, pivoted, and swept Goku's legs, sending him tumbling back — only for the Saiyan to flip mid-air and land on his feet, still grinning.

"You've gotten strong, Kai! Real strong."

Kai grinned back. "You're not bad yourself. Pretty sure your spine cracked a mountain in half last week."

They kept going — Goku pressing with stronger hits, more intensity. Kai flowed like water, dancing around him, taking some hits to sell the act, giving just enough pushback to make it fun.

All while his body hummed beneath the surface — adapting, evolving.

Hours passed. Days. They trained, sparred, recovered, and did it again. Goku practiced refining Kaioken. Kai pretended to be tired and quietly pushed his limits while meditating under amplified pressure.

One night, alone in the chamber after Goku had fallen asleep, Kai stood still at the far end of the chamber and focused inward.

He activated Kaioken again — not to fight, just to feel it.

The red energy wrapped around him. His body tensed, screamed…

Then calmed.

[Kaioken x1 Detected. Adaptation Status: Stable.]

He pushed again. "Kaioken x2."

His bones vibrated like tuning forks. His skin flushed hot.

[Kaioken x2 strain active. Adjusting spinal compression and blood pressure levels.]

He grit his teeth and went again. "Kaioken x3."

His breath hitched, vision swimming. But he stayed on his feet.

[Kaioken x3 strain adapting. Cell recovery functions enhanced. Hormonal regulation stabilized.]

"Four."

The chamber pulsed red as the energy flared outward. His body strained, buckled, twitched—

[Kaioken x4: Muscular tearing identified. Repair systems compensating. Pain receptors minimized.]

He collapsed to one knee, panting hard. His whole body burned. But only for a second.

Then the pain faded.

Sweat dripped from his brow. His heart thumped once… then steady.

He sat back, hands resting on his knees, staring at the white floor beneath him.

"I could probably push this," he whispered to himself. "Kaioken x10. x100. Maybe even a million, with time."

He paused.

"But not infinite. That's too much. I'd burn up before I adapted… and I don't know if this body can adapt to death. Or the kind of power that goes beyond what a body can even contain."

He stared into the empty white sky above.

"No matter how busted I am… I'm not Doomsday. I still die like anyone else."

He stood after a while, powered down, and returned to the central chamber. Goku was snoring with his legs over the edge of the bed, arms sprawled out like a starfish.

Kai smiled faintly. "Sleep well, Goku. I've got your back."

The Hyperbolic Time Chamber offered endless pressure. And Kai was more than happy to mold himself under it.

Because he had eight more days in here.

And the universe had no idea what was coming.