About half an hour’s careful advance later, I’m able to detect the change the Runethane mentioned. The tunnel, which until now has been semi-circular, abruptly widens and becomes rectangular. The stone’s texture changes from rough and pick-scarred to evenly tiled. When we reach the transition, there’s a step we have to go down. The echoes of our march change in timbre; they become more eerie.

“What is this place?” someone whispers, but no one replies.

I listen around to try and figure it out. It doesn’t seem like a tunnel—it’s too short and wide. It’s more like a hall than anything. This might be another fort maybe, lost to the ages, or maybe something bigger. One room of a lost palace? Or even one building of a lost city? It isn’t empty either: neatly spaced piles of dust line our path.

Whatever this chamber is, who built it? Very ancient dwarves? And how did it get to be so thoroughly sealed away without a single link to the surface, and by such smooth rock?

Before long we reach the end, a smooth wall. We stop. This is troubling—where’s the darkness, if this is the end of the passage? I hear some concerned whispering.

“This isn’t the end,” declares the Runethane. “You may not be able to make it out, but I can. There’s a door here.”

He steps up to the wall and traces two parallel vertical lines with his finger: the sides of a door; the top edge must be too far up for him to reach. He pushes hard with both palms. The door—if it truly is such—doesn’t budge at all. He lifts his mace.

“We’re going to have to break it down,” he says. He sounds like he’s relishing the prospect. “Weapons at the ready!”

“Look up there!” someone in the back ranks shouts.

We tilt our heads up to where he’s pointing. I focus my hearing, concentrate, and can make out two round holes at the top of the terminal wall. Windows, each at least as wide in diameter as a dwarf is tall.

I hold my breath—if the echoes of the dwarf’s shout are like waves beating against the wall, then the windows are sinkholes into which the waves vanish by degrees. That must be where the darkness came from. Are they its origin?

“There’s no need for alarm,” the Runethane snaps, perhaps sensing our unease. “The darkness isn’t pouring through them now, is it?”

“But my Runethane,” says Cathez, “If we all proceed through here, there is a chance it could pour up and around and attack us from behind. We risk being outmaneuvered.”

The Runethane hesitates, then lowers his mace and nods. “You’re correct, commander. We must leave behind a guard here.”

“It’s a less than honorable post, but I will take it if I must.”

“No, no. I need you with me. Belthur! You were the advance guard, now how would you like to be the rearguard?”

“Me?” Belthur says. “I was hoping for a more active role.”

“The darkness is wily, and it’s grown wilier. There’s a high chance it’ll outflank us. You will get your action.”

“Even so—”

“I am ordering you, Belthur, not asking. You and your squad will remain in this strange room, fifty yards to the rear of where we are now. Your job is to prevent us being outflanked, and also to prevent the darkness escaping should it try to bypass our force entirely to wreak havoc above.”

Belthur nods. “I understand, my Runethane. It shall be done.”

“As for the rest of us—”

The Runethane raises his mace high once again, adjusts his position so that the head is behind him for maximum momentum. He widens his stance for stability, then swings.

His execution of the blow is flawless; the mace-head moves faster than looks to be possible. It hits exactly center of the two parallel lines he traced earlier, and the stone explodes outward in a flash of light that illuminates all even through my shut eyelids. The upper half of the door crumbles down; chunks of rubble smash onto the Runethane but he barely seems to notice them. They may as well be splashes of water. Dust clouds him for a few moments, then it settles. He raises his mace again.

The narrative has been illicitly obtained; should you discover it on Amazon, report the violation.

“Onward march!”

We troop forward after him as he marches through the collapsed door. My jaw drops; shocked whispers shoot through the ranks.

“Where are we?”

“What is this place?”

“Who built it? Which dwarves?”

“Dwarves, or someone else?”

“Silence in the ranks!” orders Cathez.

We have emerged into a grid of tall corridors, stretching far in every direction. The walls are even higher than those of the room we just left, and the ceilings are arched in geometric fashion like the edges of a polygon. The floor is smooth, but not entirely so. Further mounds of dust dot it here and there, yet the black stone of the grid squares—buildings, for I see windows up high in many—bear no scars of time.

The air is very cold, and smells of nothing at all. The echoes of our voices are split by the grid layout, distorting my view of everything.

“What’s that up there?” someone near to me says.

I turn my head up and focus on where he points. The walls of the buildings have textured lines running along them. Engravings? They’re too subtle for me to make out with my hearing, so I blink my eyes open.

“What in hell!” I gasp. “Look at that! What are those?”

Now I’m the one pointing. All look for themselves at the weird etchings.

Most dwarven dwelling places have carvings or mosaics: for example, the great mosaic on the floor of Thanerzak’s forging hall depicting his victory over the dragons. Usually they depict great achievements, or the famous dwarves that accomplished them. These etchings are no different: they depict those who built this place conquering various foes, raising each other to high status, or carving out great cities.

But they are not dwarves. Each has four legs and two arms, is covered in scales, and has a crown of four jutting horns. Their eyes are narrow and their ears long and pointed, angled backwards. They do not wear armor, but embroidered clothes.

None of the etchings depict forging; instead, many show powerful looking members of this race drawing strange patterns in the air, bowing before staves and idols, and holding orbs of flickering power. A race of magicians, then.

Who were they? Or, who are they? In all the atlases of the world and underworld I’ve read, they have never been mentioned. I’ve never even heard the faintest rumor or speculation of them.

Lost to time, they must have built this city in eons past, then abandoned it—or sealed it. Slowly, the rock into which it was carved sank deeper and deeper toward the magma sea, until it plunged into it like a spear thrust into water. The black stone does not melt easily though, so the city remained intact, the darkness protected from magmatic obliteration, and now here we are.

At least, that is what I speculate in these moments of wonder and horror as I stare into the eyes of the engraved creatures.

“Ignore them!” orders the Runethane. “We seek the darkness. Whoever its creators or wielders were does not matter. Likely they are long dead—if not they will be once they run into us. We keep on marching, to wherever the center of this place is. That is where the deep darkness’s heart must lie.”

He leads us further into the grid. We walk past many doors like the one he smashed through. Each is of stone and has no hinges that I can see, and age seems to have sealed them fast. I cannot help but wonder what lies beyond each one: the darkness? Or maybe just the eroded dust of more mundane things, all that remains of the daily lives of the creatures that built here.

I’m not about to break ranks to find out. No one is; our formation tightens. Who would risk getting separated in a place like this? It’s too cold, telling me that the darkness is near, watching and waiting for us to reach too far in, to a point from which retreat will be impossible.

Very abruptly, the corridor ends and the Runethane calls a halt. He looks left and right, and nods as if understanding something we can’t see.

“We’ve reached a break in the pattern,” he says. "This looks to me like a defensive wall."

I examine it. He might be correct, but who knows? What was there to defend against in this sealed city? To me the wall just looks like an imposing slab cutting us off from whatever lies beyond. There are windows in it, high up, and further along is a plain stone ramp leading to a door.

The Runethane leads us toward the wall, where we make a right-angle turn toward the ramp. I begin to feel oddly reassured. Apart the windows at the top—which are more pinpricks than anything, like they exist to let air in and out and not much else—the wall gives a sense of enduring solidity. I’m no mason, but I can tell it’s well-carved, to a degree that any dwarf would be satisfied with.

A thought hits me: maybe the Runethane is right about this wall being a defensive one. Except it’s not designed to keep enemies out, but instead to keep them in. I look up at the windows and shiver. The darkness flowed back through them after its retreat from us, I’m sure of it.

“Halt,” orders the Runethane.

We've arrived at the ramp. It’s bigger than it seemed when we first caught hearing of it, at least thirty feet wide. There are ridges worn into its surface, like from the repeated passage of carts, and a red sandy substance is scattered over it.

And at its top is a gaping hole, where once a gate might have stood.

The Runethane bends down and takes some of the dust into his hand. He looks up to the top of where the gate would’ve been, and nods thoughtfully. There is a narrow line there, an opening.

“Never fear. This is just iron oxide. There used to be a portcullis here.”

But the air is bone-dry! How many untold years would it take for iron to rust away so completely?

“I imagine that the darkness lies somewhere beyond this point. I hereby order a rest. Take your fill of food and drink. We need sustenance, for I predict that there’ll be resistance once we pass through.”