We were on land again after having just fended off the attacks of squid-like monsters. Luckily, there were no grievous injuries. Professor Scutolith had received a line of small wounds by the clawed tentacles, but they were scratches at worst. Had he been less fortunate, the creatures might have torn open his entire right side or hit a vital artery. I had to thank my thick leather mantle for remaining entirely unscathed myself. 

Anne was patching him up, putting soothing balsam on the wounds to keep them from festering. Meanwhile, Brad and I dragged the boat completely ashore, to prevent it from drifting off should we have need for it again. After we were done, we turned to inspect the fortress wall before which we stood. 

The chamber was around thirty feet or more high where we were and the wall was almost as tall, in some places even making contact with the ceiling and as far as we could see, the chamber ended here entirely, including the lake. The wall was made form the same dark granite as the chamber itself and it closed off completely any further way on land or on water. The wall’s gates had been removed, leaving only the archway behind, most likely salvaged for materials. In front of the gate was a path chiselled into the ground that lead to what seemed like a small harbour in the lake. I assumed that this lake might have once been a shippable route before the magma from above blocked the other end off. Then this Fortress might be some kind of safe haven or toll point. But for who? And by who? 

The Professor’s wounds were taken care of and the other two joined our bewonderment about the wall before us. Brad was the first to dare bring forth a theory about this place. “Have we found some sunken continent? Osmurak maybe?” 

Professor Scutolith shook his head. “If any, not Osmurak. It still remains on the surface, mere feet below the waves of the northern waters west of Botrelandt. But how could any continent sink below the floor of the seas? And these walls were built to fill this cave, not some space under a sky. We must be at the outermost ends of some civilization's road network, maybe they have discovered this network of caves and built the furthest reaches of their empire into the most hidden crevices of the world.” He then raised his voice. “HELLO? Is anyone there?” 

The echo resounded from the naked rock walls and returned to us, not a single pebble changed or moved by the Professor’s call. We went ahead and through the gate. 

Inside was a large courtyard, even stables, and another archway, this one bereft of its gates as well. Behind it a large tunnel dug into the natural wall of the cave. Being a student of architecture, I could not help but notice certain similarities to above-ground designs. The architects of that fort had obviously mastered the simple arc and column design, with the Keystone of each and every single arch being an artwork in and of itself. The courtyard’s perimeter was a colonnade sheltered from the elements, whatever those might be; falling boulders? Dripping water? Flowing magma? Something even odder in this place? We continued on through the courtyard.  

The tunnel itself was roomy, but the doorways leading off into the fort were obviously made for smaller creatures than us humans. Brad with his barely five feet height passed through the doors with ease, the rest of us had to always duck our heads in. 

We found rooms with a set of small columns ventilation channels on the floor that suggested there might once have heated airflow beneath stone floor plates, these plates however long gone, probably also salvaged for other building projects. I could well understand the need for heating in this place and wished to sit in front of a roaring campfire myself. 

The rooms further up the carven fortress had their floors missing altogether, probably once wood suspended on beams and corbels. But if there was truly wood here, would that not mean there were trees or something very similar here as well? Maybe some form of giant fungus or lichen? Or did someone ferry wood down here through some unseen passage centuries ago? One answer seemed more logical, but the other gave hope to an escape from this dark, dead tomb. 

We explored all of the fort, finding nothing but empty rooms and a few splinters of rotten wood and remnants of tapestries and carpets. It was lunch time, but we filled our bellies with just water, refilled our cask and water skins at the lake one last time, then headed on through the tunnel the fortress was guarding. 

As we went through the gently sloping tunnel, we saw engraved on its walls scenes from when the fort might have been manned: depictions of beings, similar to humans, but with broad tails, unlike any non-human peoples I had ever seen; their bodies were covered in large, overlapping scales. At first glance I thought it armour, but they wore clothes over these scales, clothes of everyday and of ceremonial use. Their fingers were pointed and they depicted many feats of construction and craftsmanship. They presented spheres or plates to each other, all adorned with intricate designs and none the same. They worked hard to achieve perfection in masonry and they held this fortress as the highest of the high. I remember thinking they would be quite an interesting people to meet. Were they still around or were they eradicated despite their formidable fortress architecture? 

Beneath all these scenes was a script of unknown make. It was wholly different from the symbols on the heptagonal frames and Professor Scutolith again ruminated over them, noting them down quickly into his notes. 

Brad soon voiced a concern of his. “Did anyone else notice we are going down again? Should we not try to go upwards to find home?” 

The Professor stopped and after a moment of slow breathing, answered. “I can hear songs here again. Just like the lake had sung to me, I hear more songs further down. I believe there is something left for us here.” 

We tried to take this mystic statement as a thread of hope that at least one of us knew where we were headed. 

The path we walked went on further down until it came to another large natural cave. We saw a huge funnel opening on the ground before us, around which the path was carved into the vertical rock wall. Above us it stretched probably more than a hundred feet, but it was hard to see due to the clouds gathering there. Real clouds as if we had risen to the highest mountains into the skies. Below us the funnel ran narrower but also less cloudy. We could see on the walls there water from the clouds settling, first in single drops, then in trickles and finally, full streams. 

“Astonishing.” The Professor leaned over the funnel more than anyone else of us. “We seem to have come upon a weather phenomenon below the ground! Could this be how that lake came to be?” 

Around the large funnel and further down we headed on. We soon came upon a huge fissure in the wall to our right side open in a long and steep cave of natural kind. Whatever had torn open this fissure had also caused a sizeable load of rock to fall into the carved tunnel and block it. In the face of this, we had no choice but continue our journey down the fissure. 

A steady stream of water trickled through this natural cave that descended even faster than the tunnel, sometimes forcing us do slow down and find more passable ways for Chysita to descend. When we finally found a large flat area suitable for sitting down and having some rations, we used the opportunity without question. 

None of us spoke much during our sparse lunch and I instead the occasion to inspect our surroundings better. As the Professor remarked, most natural caves were formed in limestone by rainwater etching its way through cracks and then deposit their solved contents in the form of stalactites and stalagmites, but this cave was wholly void of such features, more looking like a rough fissure. The water that flowed here was also mostly clean of any solved contents, understandable if one assumed that it had evaporated and then condensed further up as that weather phenomenon. Water seemed to have carven somewhat of a gully in the bottom of the cave, requiring us to walk with spayed legs.  

At one point, Brad made a remark. “If you get lost in the wilderness, always follow flowing water and you are sure to find settlements and rescue at the end. Or the ocean.” I could tell he meant this at least half in jest, but concerning what we had found so far, I was willing to take it as a hopeful jest. 

The Professor however, seemed to contemplate these words, even stopping for a moment before turning to the golem and the rest of us.  

“She should have stopped working by now, yet here she is, hanging on, still powered.” 

I asked what was visibly on all our minds. “What do you mean by that, Professor?” 

“Chryista cannot work on her own without elemental life force saturating the air around her. Usually she’d eat an entire cask of flux within just an hour without it. She was feeding on the elemental force of the hot rock surrounding us, but we are too far away from that by now. Still, she works without problems. She speaks of a certain ‘richness’ in the air, even.” 

This contemplation took the dire and hopeless thoughts off my mind, it represented a riddle to be solved and maybe even utilized. “Is there another source below us perhaps? Layers of molten rock interspersed by porous cold rock, constituting the world like an onion or rings of a tree?” 

“I think that is a possible theory, Havellan, but there is no other evidence to believe it to be so. Let us forge on as long as lady fortune is still with us!”  

He fastened his step just when I heard Anne murmuring just below her breath. “We are going to outrun her any moment now!” A bitterness was in her voice I could well understand. For the longest part of our journey, I thought her listless and demotivated, but since I found out how much she looked after her uncle, I could understand the resentment she showed while he acted with such disregard for his own and our wellbeing. 

We found some sort of small pond where the trickle of a brook ended with no visible outflow. After carefully probing the water for any treacherous tentacled monsters disguised as rocks, we put our gear down for a short while to rest and fill our hungry bellies to the brim with water. 

Our moment of rest was interrupted by Anne letting out a scream. “IEEK!” We all shot up, ready to help or fight. “What is that!” 

The Professor hurried to her side with his vial held up high. “What happened?” 

“Excuse me, I was just startled. I put my hand on something... moist and soft.” In the light of her vial, she looked at that thing to her side. I could only get a glimpse, but I recognized it the moment she said out loud “It’s MOSS!” 

The Professor did not believe her, even though he saw the small cushion of moist green even better than I did. “Impossible! We are in lightless caves! There is no green plant that can survive!” 

We all looked at the patch of moss. It seemed not odd at all, normal as any other moss we had seen before. 

“This place is sunless, how can moss grow here?” 

With this plant being revealed to exist here, not dried out or yellow but green and fresh, my question how there could be wood down here was answered: something gave sustenance to plants. We all broke out into disagreeing discussions on the ramifications of this discovery, all of us with at least a vestigial interest in nature. Our guide Brad insisted that it was some sort of odd moss that grew on something else than light, maybe something in the water, but even he had to admit that it was no more than idle speculation. If there were plants flourishing, on light or on something else, the existence of forts with wooden floors made much more sense, as did our continued survival. 

Despite our speculations and discussions, we had to continue our trek, hoping to soon find another thing to spur us on. It came eventually in the form of light. Not our light vials or any other light vial for that fact. A slight and soft yellowness was illuminating the cave around a bent ahead. When we saw it, we rushed, we ran, careless about the risk of slipping on the dark, wet rocks. 

We came around the bend and saw before us a sight that I will remember for the rest of my life. 

A large cavern with ceilings as high as fifty feet lay before us, its walls apart by as much as five hundred feet. Suffused with light from a fog that ran along its ground, coming from another tunnel cutting the cavern from the right and running on to the left.  

High grasses, ferns and bushes grew in this cavern, bugs crawled over leaves and flew in the air, even some sort of birds dashed from wall to wall, catching the easy prey as they sailed from the rocky walls, where they clung on not just with their feet but also their wings. 

We stood there, unable to believe our eyes. 

We had come upon a forest beneath the seas, beneath the rocks, beneath the very fiery bowels of the world themselves. Expedition, discovery, return, all seemed meaningless in this new world we had found. For now, this view was enough to cling on to.