"Do not test the depth of the river with both feet." 

While waiting for Pendra to return, I carved five more stones with varying patterns, phonetics, and images to dictate my intent. I also experimented with different styles of geometric borders, hoping none of them would blow us all up.

In hindsight, treating volatile energy like a trial-and-error science experiment was a horrible idea. That was exactly why I waited for her. If things went wrong, I needed her to throw the stone far away.

There were far too many ifs and maybes for my taste. Cultivators had been here ten thousand years ago, but the Jötnar had systematically hidden or destroyed their knowledge. It couldn't be entirely lost, though. Since the Jötnar couldn't enter a Rank 4 or higher Spirit Beast’s gravity well, sanctuaries had to exist. The question was simply how to find them.

I shook my head as Pendra scaled the pillar, dropping two Rank 2 centipedes at my feet. But it was her third catch that made my eyes widen. It looked like a crab with stunted claws and a stony, grey carapace. What drew my attention, however, was the mushroom farm blooming on its back. I almost cried, but I swallowed the emotion down.

Finally! Something that looked like food.

The mushrooms were small, pale buttons with thick, rubbery stalks, growing in a dense, overlapping cluster across the crab's calcified carapace. I leaned in close, my nose twitching. No smell of rotting copper. No stinging, chemical off-gassing of alkaline sap. They smelled earthy. Like damp soil and rich rain. For an ethnobotanist trapped in a literal hellscape of toxic waste, it was the most beautiful scent in the world.

The crab was dead, its nervous system thoroughly scrambled by the venomous stingers on Pendra’s back arms, but the fungal colony was perfectly intact. It was a classic mutualistic symbiosis. The crab’s shell likely secreted a calcium-rich mucus that neutralized the local Rot Qi, creating a tiny, safe micro-climate on its back. In return, the mushrooms masked the crab’s scent from larger predators. Nature always found a way to carve out an equilibrium, even in a garbage dump.

I carefully sliced a mushroom at the base with one of my acupuncture needles. A white, clean, milky sap beaded on the cut. I touched a microscopic drop to the tip of my tongue.

Nothing. No chemical burn. Just pure, clean starch and an overwhelming hit of glucose.

I didn't gorge myself. I couldn't afford to. My stomach was shriveled, and a sudden influx of complex sugars could throw my system into refeeding shock. I ate three small caps, chewing slowly, letting the raw calories dissolve under my tongue. The effect was immediate. It wasn't the violent, dry heat of the mud pills that forced my bone marrow to ache. This was just raw metabolic fuel. I felt a faint trace of Qi as well—similar to the mud pills, but on a much smaller, manageable scale. My hands stopped shaking, and the dull fog in my skull began to clear.

With actual glucose firing my synapses, my brain spooled back up to full capacity. Feeling steadier, I looked at the five carved stones lined up on the resin ledge.

It was time to see if my code compiled.

"Pendra," I communicated through the tether, projecting the physical motion of throwing along with a sharp sense of distance and caution. "Take this. Throw it to the eastern corner. Far."

She tilted her head, her mandibles clicking as she picked up the first stone—the one etched with the mycelial expansion lattice and the strict square boundary. Her clawed arm flexed with visible muscle tone, and with a sudden, whip-like snap of her torso, she launched the stone into the dark abyss of the lower tunnel.

Two seconds of silence. Then, a sharp crack as the stone shattered against the far wall.

Instantly, a muffled, wet thwack echoed up the massive cave.

I closed my eyes, routing a microscopic thread of energy to my retinas to reveal the residual Qi in the air. The compressed energy locked inside the chitin etching had read the geometric boundaries perfectly upon impact. It didn't explode in a random blast of raw force. Instead, the ambient Rot Qi in the tunnel was violently dragged toward the impact point, instantly forming the biological intent I had imbued in the image of the cellular lattice.

I scrambled to the edge, climbing up Vane-Uru’s massive husk to get a better vantage point.

A massive, perfectly square wall of dense, fibrous blue mycelium completely choked the eastern corner of the rock field, opposite Vane-Uru. It was exactly four feet wide by four feet tall, matching the rigid crosshatch geometry I had etched. The edges were clean, compressed so tightly by the square boundary that the fungal threads looked like solid timber.

It worked. The geometry hadn't just directed the growth; it had acted as a physical pressure valve, containing the energy until it took the exact shape I commanded.

"The code compiled," I whispered, a manic, exhausted grin tugging at the corners of my mouth. Even with the food, I was still feeling mentally burnt out.

But looking at the barrier, my thoughts drifted back to the puzzle of the Jötnar. If the giants couldn't enter the high-gravity wells of Rank 4 or higher Spirit Beasts, then those hyper-lethal zones weren't just monster dens. They were time capsules I needed to find. The Jötnar had systematically wiped the surface clean of human cultivation history to keep humanity weak and out of other cultivators' hands, but they couldn't scrub the deep trenches.

If any uncorrupted, ancient manuals existed—schematics that showed how the human body was actually supposed to filter and compress Qi without destroying its own pathways—they would be down there. In the dark, protected by things that could crush a giant.

That part bothered me.

I was under no illusions about my combat potential. I was not a fighter; my strengths were logistics, command, and the space between my ears. It was rarely wise to rely entirely on another's strength, but I had Pendra. I had no plans to become a sword saint—but turning her into one? That was a project I could get behind.

I looked down at the remaining four test stones, then at Pendra, who was tearing into one of the Rank 2 centipedes.

I had food. I had a working defensive tool. My body was physically denser and strong enough to withstand the pressure of a deeper descent.

Once I tested these other stones, it was time to stop hiding on a pillar and go find an archive.