I Became the Magic Tower Master's Experimental Mouse - Chapter 1

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This chapter was translated by Lunox Novels. To support us and help keep this series going, visit our website: LunoxScans.com
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Acrid poison smoke scraped against my lungs.
“Cough…….”
Amid the collapsing flames of the Tower of Poison, I suddenly recalled the sharp, earthy smell of soil.
The Underground Burrow.
Our quarters—a long shaft burrowed deep beneath the ground.
* * *
Children lived in that burrow.
Every day beaten with whips, clutching empty bellies, huddling together for warmth so we wouldn’t freeze to death in that underground darkness.
“I’m like a centipede.”
“Then I’m an ant!”
“And I’m a mole! My grandfather used to call me that all the time…….”
One thoughtless child’s mumble had silenced the burrow in an instant.
Soon after, the sound of stifled sobs echoed from every corner.
“……I want to go home.”
“M-Mom…….”
Beneath the minimal lighting installed to keep the children from going blind, sorrow spread like contagion.
I’d been lying down, but I suddenly sat up.
“But they’re teaching us how to throw and wield a blade here.”
As I scrambled to find some silver lining, a boy’s voice cracked with tears.
“They’re doing that to turn us into assassins.”
“But……if we only grieve, everything becomes even more sorrowful and bitter, doesn’t it?”
My Grandmother had left me with that wisdom: laugh harder when you hurt the most.
“Let’s all pass the Selection Test together and form an Assassin Mercenary Company! We’ll earn a fortune and go back to our Hometown.”
At my words, the children fell silent again—but this time imagining themselves wealthy and refined.
“I hope so…….”
Someone’s fragile voice drifted through the dark.
* * *
“Look at this! I found a mushroom. That’s pure luck, right?”
I returned to my spot triumphantly, holding up a fluorescent-glowing fungus.
The boy whose back had split open from whipping bristled immediately.
“Are you insane? How is that luck! That’s a poisonous mushroom!”
“I can eat it without dying. Now I have something to give the older kids for tonight’s meal.”
I giggled and handed him a gruel-like porridge I’d made by boiling earth.
At first, not knowing any better, we shared the plants that grew in this place, and three children died from it.
After that, I was the only one in this burrow who could eat what grew here.
“For a runt like you……you’re an idiot.”
When I held out my own portion of food, his face contorted as if he’d burst into tears.
We had each other. Yet the children kept dying.
From illness, from accidents during training, from wasting away and collapsing.
The burrow’s door opened only at dawn and dusk—when training began and when they sent us back.
The ladder had to be lowered from above for anyone to grab and climb out, so no one even thought of escaping.
“You’ve been weeded out quite a lot. Tomorrow morning, I’m taking only the ones still breathing. Only three of you will survive.”
One day, weapons fell from the ceiling.
Short Swords, poisons, various arms we’d been trained with—scattered across the floor.
‘But we said we’d all get out together…….’
I don’t remember what happened after that clearly.
When the door opened at dawn, I was one of the few children standing there in a daze.
* * *
I learned only after escaping that there were countless burrows like ours. We had been just one group among them.
And even if you survived this training, two out of three usually died on the first assignment.
After my first assignment, I stumbled back having bled so much the world had turned white.
“You made it back.”
“A rat-ling’s hardy, I suppose?”
Someone chuckled dryly and dropped a coin purse at my feet.
I picked it up and clutched it to my chest.
I had survived.
My life was no longer mine alone.
The deaths of every child in that burrow weighed upon it.
For their deaths not to be meaningless, I had to become, at the very least, the greatest assassin there was.
‘That’s right. I’m the lucky one.’
Small, insignificant rodent, a winter dormouse hybrid whose only virtue was speed.
Yet somehow, I was the only one who survived.
A dream of one day founding an Assassin Mercenary Company, growing wealthy, and returning to my Hometown…
Even if I couldn’t see that dream through, at least I had to leave something behind as an assassin.
* * *
‘Is this the Lantern of Life?’
But death came for me too, with perfect impartiality.
Acrid poison smoke filled my lungs.
This was the Tower of Poison. The place where I’d taken my final assignment.
Crimson flames and toxic fumes closed in from all sides.
“This can’t be…”
I had something I needed to do here.
Guard the Tower.
For that person and for everyone—a task I absolutely had to complete, even if it meant giving my life.
But I was dying without having finished it.
The Tower was crumbling, consumed by flame, and I lay on the ground unable to do anything but weep tears of regret.
‘…Is this how it ends?’
All my stubborn perseverance, and this is what I get.
‘I don’t want to die yet! There’s still work left to be done!’
Bitter remorse and a crushing sense of duty held me to the very last flicker of consciousness.
But in the end, I died.
* * *
Sniff, sniff.
The warm, familiar scent of Grandmother reached me.
The smell of medicinal herbs she used to brew when I was ill, drying in the air.
The blanket covering my body was quilted by Grandmother’s own hands.
Her hands were rough and clumsy.
She never learned fine stitching, so the blanket had loose threads poking out here and there.
Still, whenever it grew cold, as I spent whole days curled up sleeping, Grandmother would drape that blanket over me.
‘Little rats die when they’re cold. Keep it on.’
The moment I caught that scent of Grandmother I’d forgotten so long ago, the memories came flooding back.
My ears perked up of their own accord, joy welling inside me.
What’s more, my body felt incredibly good.
Years ago, I’d suffered an internal injury during a mission, and every breath brought a dull, persistent headache.
Now there was no pain at all!
“Heaven…?”
I muttered absently, flexing my arms this way and that.
No, it couldn’t be heaven.
If it were heaven, Grandmother would be here.
A place of peace without pain.
A place where gold and jewels rained down and beautiful men and women greeted you with kindness.
A place where you reunited with the dead.
As someone as familiar with death as an assassin, I’d been exposed to various teachings about heaven many times.
But I’d never heard of a heaven like the one I found myself in now!
‘…This is supposed to be heaven?’
Impossible!
What kind of heaven makes you younger!
The reason my body felt so good was absurdly simple: the pain hadn’t vanished because I’d never been injured in the first place—I had the young body of a child who’d never suffered a wound!
“My muscles…”
The lean, muscular frame built by years of training had completely disappeared.
All that remained were soft, pudgy forearms and chubby cheeks.
The tail I’d had cut short during training days because it was hard to hide—I could feel it again now.
My winter dormouse tail, thick with its distinctive fluffy fur, draped across my thigh and swayed gently.
I looked down at my stubby, compact little body and frowned.
‘That’s…’
A long, vertical scar ran down my leg. It still bore a red tint, as if it had formed only recently.
On my sixth birthday, when I heard that Grandmother—who’d raised me—had met with an accident, I rushed out and took a bad fall. That’s where this scar came from.
This wound would eventually scar.
Which meant…
“You didn’t grow weaker—you’ve come back, haven’t you?”
The realization hit me like a shock of cold water.
Six years old. And I’d come back ten years.
This was really…….
“This is amazing……!”
I cried out, dazed.
I couldn’t recall the final moment with perfect clarity, but the thought ‘it’s over’ had been vivid enough.
And along with it came a tide of overwhelming regret.
‘……Wait a moment.’
The thrill of the Regression faded quickly. A strange unease crept over me.
Something was wrong with my memories.
The sensations before death—the despair, the acrid red poison smoke swallowing everything around me, the flames, the way strength drained from my limbs and chills racked my body—all of it remained disturbingly vivid.
But the most important thing.
What was I doing in the Tower of Poison?
‘……Why did I want to protect it?’
I couldn’t fathom why an assassin like me would have thought to defend the Tower of Poison, yet strangely, I had no memory of it at all.
As if someone had carved away every memory connected to that tower.
‘It makes no sense—I’d never have wanted to protect something like that.’
The Assassin Guild would never assign me a defensive mission.
So I must have decided to protect it myself, then…….
‘Me? When there’s no profit in it?’
Was there something in that tower important enough for that?
And the missing memories troubled me even more.
The target’s patterns, the timing of guard rotations, the angle of each throw…….
I’d been trained never to forget anything I saw once.
Yet I’d forgotten the final moments of my entire life.
‘……That doesn’t add up.’
No memories, but the feelings—they remained brutally sharp.
The weight of duty, the sting of having failed to protect—I could still feel them, raw and fresh.
A cold shiver ran through me. I slapped both cheeks and shook my head.
“No. It’s fine.”
I’d been given another chance to change the things I regretted in that life gone by!
‘I really am lucky.’
I forced out a laugh—a deliberate, almost manic sound.
And I began to think about what I most wanted to change from my years before.
It was the day I’d been kidnapped into the Underground Burrow, forced to become an assassin. And that final moment of death, consumed entirely by regret.
‘I have to escape.’
I had to avoid being taken to the Assassin Guild at all costs.
But simply avoiding the Burrow wouldn’t be enough.
‘……I need to know.’
Why I died in the Tower of Poison.
Why I couldn’t protect it—and why the failure haunted me so completely.
Which meant there was only one place I needed to go.
‘I’ll go to the Tower of Poison.’

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This chapter was translated by Lunox Novels. To support us and help keep this series going, visit our website: LunoxScans.com
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