Where the highway ended, we switched from carriage to foot and stepped into the forest.
The path was little more than a rugged animal trail, barely worthy of the name. I could smell the damp earth and hear the rustle of leaves brushing against one another. Overhead, the thick canopy of branches blotted out the sun, leaving the woods shrouded in a midday gloom.
As we navigated the rough terrain, the trees eventually thinned, revealing a small clearing.
Nestled in the back of the space was a small hole—our destination, the labyrinth.
"It’s... a bit smaller than I expected," Lene said with a wry, involuntary smile.
"After seeing the Primal Labyrinth, I suppose anything would look small," I agreed, turning my attention toward the entrance.
To be honest, its scale was underwhelming. It looked like a simple hollowed-out pit in the ground, and it didn't seem to have much depth. If someone had told me it was just a hole dug by a child for a prank, I probably would have believed them.
Of course, its depths were veiled in a darkness that prevented me from seeing all the way in. Mana pulsed from the opening, and I could sense the distinct presence of monsters.
It was a labyrinth, without question.
However, it was nothing like the Primal Labyrinth—that abyss-like Great Hole that felt as though it led straight into the pits of hell.
(I suppose it just goes to show exactly what kind of dangerous places we’ve been throwing ourselves into.)
As I stood there observing the entrance, I heard a dull thud behind me.
Turning around, I saw Rio dropping her massive backpack onto the ground. The luggage was disproportionately large for her petite frame. She let out a soft sigh, then knelt and began undoing the buckles with practiced ease.
"Well, of course it is. This is just a D-Rank Labyrinth, after all," Rio said, pulling open the mouth of the pack.
She retrieved a small metal device, followed by several magic stones and various small components, which she lined up neatly on the grass. As she began to assemble them with dexterous hands, she continued.
"I wouldn’t dream of testing my work in a place like the Primal Labyrinth—that monster—right from the start."
The magic stone clicked into place with a dry snap. She then connected it to a rod-shaped component with a sharpened tip and traced the etched patterns on the surface with her fingertips, channeling mana into them. A faint light raced through the circuits of the rod, spreading across the entire device.
"In theory, the design is perfect," Rio said as she worked. "But there’s a lot you can’t know until you actually use it. Mana fluctuations, coordinate drift... those fine details can only be confirmed through a field test."
She paused, glancing up at me.
"That’s why we’re starting with a D-Rank. That way, if anything goes wrong, we can still make it out, right?"
Her smile gave me a momentary flash of unease. In the original story, Rio was dead. That meant that eventually, the "anything" she mentioned would inevitably happen.
I turned back toward the hole. It was just a tiny, insignificant pit in the middle of a forest.
(This shouldn't be the place.)
The Rio Krausel of the original work had lost her life in a different labyrinth. It had been a high-difficulty dungeon that manifested suddenly in another location. During her experiments there, she had been ambushed by monsters, and her magic tools had failed to work as intended. She never made it home.
That was her ending in the game.
(If there really is such a thing as fate...)
Rio would eventually reach that place. She would find her way to the very labyrinth where her life was meant to end.
She was Albert’s granddaughter—a kind-hearted engineer even he recognized as a genius. Because she wanted to save lives, she wouldn't hesitate to dive into a dangerous labyrinth even knowing the risks. If the destiny for a girl like her was to die alone in the dark...
(Then I'll just crush that fate myself.)
It was as simple as that.
"Done! It's finished!"
Rio let out a cheerful cry as she tightened the final fastener, nodding with satisfaction. She stood up and held the completed device out for us to see. It looked like a long, slender metal stake. The bottom was pointed for driving into the earth, while the top featured a small pedestal where an embedded magic stone pulsed with a soft light.
"This is the device that fixes the escape coordinates—the Coordinate Stake."
She demonstrated by thrusting it into the ground. As it sank deep into the soil, the magic stone at the top flared to life, as if a switch had been flipped.
"Once this is set, the mana coordinates of this location are locked. And then..."
Rio rummaged through her backpack again, this time producing three bracelet-style magic tools. They looked like oversized wristwatches, but instead of a dial, they contained a small magic circle and a needle resembling a compass. The outer rim was lined with crushed magic stones that cast a dull glow.
"This is the Return Device!"
She slipped one onto her wrist and continued her explanation.
"The needle is designed to always point toward the Coordinate Stake. If you channel mana into it, the device teleports the wearer back to those exact coordinates!"
She gave a mischievous "Nishishi" grin, showing off the dial, then handed the other two to us.
"Here! One for each of you!"
I accepted the bracelet, raising an eyebrow. "You’re quite the over-preparer."
"Obviously!" Rio said, looking proud of herself. "You never know what might happen. Making spares is the absolute basic of basics!"
Sounding every bit the professional engineer, she handed the final bracelet to Lene.
"Thank you very much!" Lene said.
"You’re very welcome." Rio nodded happily, then held up a finger. "But listen—don't lose them, okay? These are still prototypes, and I don't have any more spares."
Though she was smiling, her eyes were dead serious. I nodded and strapped the bracelet on. The metal casing was rugged, housing the small, dimly glowing magic circle in the center. The needle swayed slightly like a compass, but it consistently pointed toward the Coordinate Stake.
(A Return Device, huh?)
In CHOICE//MAZE, these magic tools were introduced in the middle of the story. They were effectively the lifeline of the students—The Chosen.
Of course, this version wasn't quite the same. The ones in the game were much more refined. Compared to those, this prototype was clearly unpolished. It lacked any ornamentation, the casing was blunt, and the needle's movement was slightly unstable. The central magic circle glowed far more faintly than the final version. It looked every bit the prototype.
Regardless, it was still a functioning escape device.
"Well? Is it pointing toward the stake?" Rio asked expectantly.
"Yeah, it is."
"Hehe. See? I told you."
She beamed at my honest answer. Lene giggled softly at the girl's innocent reaction.
"It truly is amazing, Rio-san. If you can create a return point outside a labyrinth and teleport back to it... provided it's stable, it would completely revolutionize the safety of exploration!"
"Right?" Rio leaned in eagerly. "People always wait too long to decide to retreat. But if they know they can escape in an instant, they’ll stop taking unnecessary risks. It makes transporting the wounded easier, too. It could prevent so many tragedies!"
She paused, her expression turning slightly more focused. "...Assuming it works according to theory, anyway."
"Don't go getting timid on us now," I said.
"I'm not being timid! I'm just performing the standard checks an engineer has to make!"
Rio pouted at me, and I let out a soft chuckle. She was right, of course. No matter how sound the theory was on paper, you couldn't account for the variables of the field without testing them. That was the whole point of today.
This D-Rank Labyrinth was significantly less dangerous than the Primal Labyrinth. Even if the unthinkable occurred, Lene and I could handle it. It was the perfect testing ground.
"Okay, final briefing," Rio said, pointing a finger at us like a schoolteacher. "First, always keep an eye on the needle inside the labyrinth. Second, when you use the teleport, don't panic—just flow your mana steadily. And finally..."
She paused for a beat, a smirk playing on her lips.
"If things look dangerous, we bail immediately. Today’s goal isn't to clear the place; it’s an experiment."
"If it even comes to that," I said, shrugging.
Rio blinked at me for a moment, then her smirk widened.
"Ooh, look at you, Mr. Confident!" She playfully patted my shoulder. "Then I’m counting on you, Strongest! If anything happens, make sure you protect me, okay? After all, I’m just a delicate girl."
I couldn't help but smile at her lighthearted tone. It was a complete transformation from the girl who had been so dejected after the fight with her grandfather. At the very least, if she was back to cracking jokes, she had recovered.
"Yeah. I've got you covered."
Rio nodded, satisfied with my short answer.
"Alright then—let the experiment begin!"
She spun around and marched toward the labyrinth with a light step. We followed close behind as Rio headed into the dark, gaping maw in the forest floor without a single trace of fear.