Chapter 421: Does Causality Law Affect the Universe?

Qin Hao opened his eyelids.

What met his eyes was not the familiar warship command cabin, but a recuperation room.

"Vital signs are stable, consciousness fluctuations have returned to normal."

An electronic tone sounded in his ear.

Immediately after, a slightly gaunt face loomed into his line of sight.

Qian Yin.

This usually decisive chief scientist now had faint dark circles under her eyes.

"Awake?"

Her voice was gentle.

"Mm."

Qin Hao wanted to speak, but found his throat as dry as having swallowed a handful of sand, only able to utter a monosyllable: "Water."

A straw was promptly brought to his lips.

Warm liquid slid down his esophagus into his stomach, and Qin Hao felt he had finally come back to life.

He tried moving his fingers; fortunately, the parts were all there, sensation normal, but the feeling of being drained of strength lingered.

"How long have I slept?" Qin Hao asked.

"Three days."

Qian Yin set down the water cup, her fingers flying across the holographic screen beside her, streams of complex data cascading down,

"Precisely, it's 74 hours and 21 minutes. Your body is practically a freak; that degree of energy overdraft,

would have caused genetic collapse into a puddle of mush in any other carbon-based lifeform, yet you merely… slept."

Although she called him a freak, her tightly furrowed brow finally relaxed.

Qin Hao tugged at the corner of his mouth, trying to smile, but moved the stiff muscles in his face: "Who am I? A calamity left for a thousand years?"

"Glib-tongued."

Qian Yin glared at him, then seemed to recall something, her face slightly flushing, her gaze somewhat evasive,

"That… earlier on the battlefield…"

"Which?" Qin Hao asked knowingly, his gaze burning into her.

Qian Yin bit her lip; the usual defiant female scientist was gone, replaced by a maidenly demeanor.

After a long pause, she stammered: "You said… after we kill it, we would…"

"Marriage."

Qin Hao took up the cue, his eyes becoming dead serious, shedding his playful smile,

"I remember every word. What, you want to back out?"

Qian Yin froze for a moment, then burst out laughing with a "pfft."

She leaned forward, lightly embracing Qin Hao, her cheek against his chest, listening to his strong heartbeat.

"No regrets; whoever regrets is a puppy."

A warm atmosphere flowed through the ward.

But Qin Hao is a master at killing the mood, or rather, the system in his mind is a master at killing the mood.

【Alert! Aftereffects detection report for causality law weapon use has been generated; please host, check immediately!】

Qin Hao's eyes turned cold; that warm tenderness vanished instantly. He gently patted Qian Yin's back:

"Yin Yin, I want to eat something; could you get me some beef? Extra spicy."

Qian Yin raised her head, though she wondered why Qin Hao, just awakened, wanted such heavy fare, but she nodded:

"I'll arrange it; don't move around."

Watching Qian Yin leave the room, Qin Hao's smile completely disappeared.

"System, pull up the report."

Swish.

On his retina, the system interface that was originally azure now bore a layer of eerie dark red.

【Causality Law Interference Assessment Report】

【Side-effect Feedback: The self-consistency of cosmic operational logic is impaired】

Qin Hao frowned: "Huh? What kind of side effect is this?"

The system didn't respond to his grumble, but directly unfolded a massive holographic star map before his eyes.

It was a real-time star map of the Laniakea Supercluster.

【Please host, observe the end of the Centaurus Arm, designated X-799 star system.】

Qin Hao focused his gaze there.

In his memory, it was a middle-aged yellow dwarf star with a habitable planet.

On it had arisen a civilization just entering the steam age—the Gear Clan.

The exploration team of the Yanhuang Civilization had visited there a year ago, leaving observation records.

But now, the star map showed a red giant star rapidly expanding.

Its volume had swollen hundreds of times, its outer flames already engulfing the orbit of that habitable planet.

"What's going on?"

Qin Hao's pupils contracted slightly: "This star still has at least four billion years of lifespan; how could it suddenly enter its decline?"

【Because it is affected by causality.】

The system explained.

That strike, although it was you who swung it, but conservation of energy and conservation of causality are the iron laws of the universe.

You forcibly defined the Overlord's 'death,' and the universe, in order to maintain a logical closed loop,

must draw 'life' or 'time' from elsewhere to fill this huge gap.

This is a disordered, random compensation.

The time of the X-799 star system has been 'advanced' by four billion years to offset one‑trillion‑trillionth of the causal backlash from that strike.

Qin Hao's fingers instinctively gripped the bedsheet.

This isn't compensation—it's literally robbing the east wall to patch the west wall! And it's someone else's wall!

That Gear Clan civilization hadn't even gotten a glimpse of the starry sky before it was silently wiped out?

Just because I swung a blade?

This is merely the physical aspect.

The system then dropped another bombshell.

Please examine the historical records of the Ge Si civilization.

The scene shifted.

The Ge Si civilization—a race resembling Godzilla, honest and simple‑natured—is a key member of this allied force.

Qin Hao clearly remembers that, according to the Ge Si civilization's historical records, their homeworld split due to crustal movement, thereby giving rise to life.

But at this moment, the latest 'General History of the Ge Si Civilization' scan displayed by the system shows that the first chapter's content has changed.

No longer 'crustal movement,' but—

"In the primordial era, a void‑blade that pierced the star river cleaved the homeworld; mysterious energy rained down, giving birth to our ancestors…"

Qin Hao felt a chill run down his back.

"History… has been rewritten?"

The causality‑law weapon affects not only the present, but also ripples into the past and future.

The Overlord died by the causality law; to make this event 'reasonable,' the universe automatically corrected the related segments of the causal chain.

Although this correction now focuses on minor details and does not alter the overall situation, just as a butterfly's wing flap, if such tiny deviations keep accumulating…

"What will happen?" Qin Hao asked in a low voice.

"The universe might deem the current timeline an 'error code' and thus trigger… an antivirus program."

The ward fell into dead silence.

Qin Hao closed his eyes, and that earth‑shattering strike rose in his mind. Back then he felt only exhilaration, as if it were a hymn to human courage.

Now it looks more like an ignorant child holding a loaded gun.

He won the war.

Yet on the universe's flawless porcelain, he knocked an invisible crack.

"Is this the price of causality…"

Qin Hao muttered to himself, the shock in his eyes fully subsiding.

"Yes, the causality‑law weapon involves the operation of the entire universe; even high‑level civilizations that have mastered causality technology dare not use it lightly."

Hearing the system's explanation, Qin Hao finally understood.

But since it's already done, there's no regret medicine to take.

Whether it's the Overlord or the so‑called universe antivirus program.

Whoever tries to harm those he cares about, or destroy the hard‑won peace of his home, he will cut them down.

If one strike isn't enough, then two.

If causality seeks to backlash, then we'll trample causality itself underfoot.

The room door opened again.

Qian Yin walked in carrying a tray, the aroma wafting over: "The beef is here, plus the extra spicy you wanted."

She saw Qin Hao leaning against the headboard, his deep gaze fixed on the vast starry sky outside the window, his expression unnervingly calm.

"What's wrong? Are you feeling unwell?"

Qian Yin keenly sensed that something was off.

"Nothing."

Qin Hao turned his head, putting back on his relaxed smile,

"Just thinking, this universe is huge; if we ever go on a honeymoon, we should pick a better spot."

He took the tray, ate big mouthfuls of beef; the spicy flavor stimulated his taste buds, making him feel truly alive.

As for those hidden dangers… for now he can't attend to them.