Summer’s eyes swept the fortress. “One of them has to be close.”

I nodded, trying to listen, as my eyes followed the falling blaze rod.

That could have been me.

Just like with the magma cube, I’d allowed myself to get overconfident.

“Off we go,” trumpeted Summer, trotting down the nether brick road.

Trailing in her wake, I tried to keep track of all our threats. Ghasts, blazes, one wrong step over the guard…

It was all I could do to keep focused, to not be distracted by the sheer complexity of this towered labyrinth before us. How had she done it? Conquered two of them all by herself? Just that fact alone gave me the confidence to follow her every step.

Thf-thf-thf!

“On the left!”

At her warning I stopped short, as the three flares passed between us.

Smoke! Out of the corner of my eye.

Thf-thf-thf! I sidestepped this time, bringing around my bow.

“Don’t shoot!” I paused in confusion as Summer beat it for the intersection. “We’ll lose the blaze rod if we don’t lead it over solid ground!”

I followed, then halted abruptly as another volley crossed our path. Then we were off again, stopping at the intersection, turning to fight as the spinning hunter hovered up and onto the catwalk.

Summer shouted, “Now!” Her sword glinted in the gloom. “No more wasting arrows!”

“Are you…” I don’t know if the last word would have been “kidding,” “serious,” or “crazy,” but none of them had come out before she charged our enemy.

“C’mon, Guy!” she called over her shoulder. “We’ve got ’im!”

What a sight, even from my running, shaky vantage point. Summer the Slayer, with courage born of endless experience. She dodged and weaved, and then, when she was just underneath it, gave a high, slicing leap! Her blade struck with a less-than-dramatic clink, and in two follow-up strokes, it was all over. I gave a whooping cheer for her performance.

“Thank you!” Summer emerged from the dissipating smoke with a yellowish orange stick. “One blaze rod to go.”

“That’s what powers the brewing stand?” I asked.

“And can be turned into blaze powder for strength potions,” she answered, stowing the rod in her pack. “And there’s plenty more where that came from.”

Summer motioned to another structure farther down the catwalk. Unlike the open “doorway” towers, this column was capped with an enclosed structure. I could see barred windows and a fenced-off roof. I could also see that the roof nearly scraped the cavern ceiling, and that something was flickering in the narrow, open space.

“There’s the spawner,” Summer announced, and took off with me in tow.

Don’t spawn, I silently prayed as we ran in the opposite direction of safety, please don’t make any more of those…

No such luck.

With roughly twenty blocks to go, I saw the flaming little cage breathe a blaze to life.

“Faster!” cried Summer, darting into the empty structure below it. It was some kind of garden, with two rows of soul sand sprouting large, red mushrooms—different from what I’d seen on the surface.

I didn’t have time to examine them, or even ask what they were. Our goal was the staircase that rose between the two plots, and the newly spawned blaze that waited at the top.

This time, Summer didn’t charge. She waited for a moment at the first step. I could see her eyes darting across the dark purple roof. Was she trying to locate our target by sound?

I’d thought blazes were completely quiet, but soon realized I just hadn’t been close enough to hear them breathe. It was a really creepy sound: slow, labored, and slightly metallic, like someone trying to suck air through a pipe.

“Hhhuh-hhhoh-hhhuh-hhhoh.”

“Still just one,” she noted calmly, eyes lowering to the stairs, “and if it won’t come to us…”

Off again, bounding up the stairs with a cry of “Keep up!”

“Can’t wait!” I huffed sourly, bursting onto the roof just as a rotating fiend turned toward us.

Thf-thf-thf!

Summer and I parted quickly, giving the fireballs a wide berth.

“Quickly!” she shouted, racing for the blaze. “Before it gets away.”

I think she meant hover off the roof and out of sword range. I personally wouldn’t have minded its getting away, especially before another blaze puffed into existence. But I didn’t argue or hesitate. The impact off my blade sounded, and felt, like I was striking metal. I could feel the hard crack reverberate through my hand.

A few short blows from both of us was all it took to give that blaze the blues.

Okay, so maybe I still need to work on my wit, but you get it. We took it down so quickly and easily that I had more than enough time to turn my attention to the spawner.

“No, wait!” Summer’s words caught my pickaxe mid-swing. “Don’t destroy it!” She held out a handful of netherrack. “Just seal it in. Hurry!”

Urgently, she began blocking up the narrow space between the roof’s fence and the overhanging land. I followed suit, asking, “What could we possibly gain by—”

Another tortured “Hhuh-hhhoh,” with Summer and me only halfway done. I turned to face a newly spawned blaze.

“Summer!”

“I know!”

Her blade had already fallen, making her the burner’s target. I reached for my sword and accidentally pulled out my pickaxe, but saw that I didn’t have time to switch. Summer leapt sideways as sparking triplets hit the fence behind her. I struck, hard and fast. Summer followed with a frontal assault. The blaze let out a final, groaning gasp, then vanished into a smoking rod.

“Finish the job!” Summer swiped up the rod and ran back to seal up the spawner. I continued on my end, counting the seconds until another blaze showed. Luckily, by the time we heard the breath of a new, living blowtorch, Summer was fixing the last netherrack block to the staircase.

“Right then!” She gave a long, deep sigh, then preempted my question with: “I know what you’re thinking: Isn’t it dangerous leaving that monster maker up and running? But blaze rods are what power brewing stands.” I remained silent, so she followed up with, “So even when we leave the Nether, we’ll still be able to come here to get more for potions.”

It made sense, in the moment. But I’m sure if I had really thought about it, as I did much, much later, I might have wondered if it actually made more sense to just stock up on enough obsidian to make portals to visit the Nether for whatever we needed when we needed it later, after we were on the move.

But I wasn’t really thinking about it. And unlike my previous, solo life on the island, when any time was a good time for a mental puzzle break, I was still junior partner in a mission that was nowhere near over.

So, with a trusting “Okay,” I followed her back down the stairs and into the dark passage beyond. “Don’t bother with the nether wart,” she said, gesturing to the garden.

So that’s what nether wart looks like.

“I grow them up top. And besides”—she hesitated at the hall’s entrance—“too many other goodies stashed about.”

Just then my night vision began to wink out.

“Uh, Summer…”

“Me too,” she answered, reaching for another bottle. “Time to top off.”

I did likewise, noticing my dwindling inventory. “One left after this.”

“All we’ll need,” she declared, striding confidently into the corridor. “One glowstone harvest, and maybe a few bonus goodies, and we’ll be on our way.”

She stopped at the first intersection, turning back the way we came. “But first…”

I watched her take a crafting table from her belt, place it on the floor, then whip up a signpost marked “Home.”

“Just in case we lose our way.”

She really knows what she’s doing, I thought, following her farther down the passageway and down another flight of stairs. I noticed that the barred windows here looked out onto solid netherrack, and when I asked if we were underground, Summer explained that parts of these fortresses were embedded in the surrounding land.

“Easier to get lost,” she said, placing another signpost, “but at least you don’t have to worry about ghasts and blazes.”

Summer was a few steps ahead of me by then, turning right around a corner.

I heard an exultant “A-ha!” and a second later, saw the reason why.

Farther down the hall, just before another turn, was a standard storage box that seemed as out of place as us.

“Fancy some treasure?” she asked, and bounded forward with a lighthearted skip.

Treasure! So that’s what she’d meant by “bonus goodies.”

And they were!

Summer pulled out a handful of gold ingots, then a pair of sparkling diamonds.

“Whoa,” I breathed, then asked, “Can you mine gold and diamonds down here?”

“Not that I’ve found,” answered Summer, which, naturally, got my mind working overtime on the big “Why?”

Why were they here? Already mined and processed and placed in these chests? Who did that? And for that matter, who built these fortresses to begin with? Like the mine under my island, had they been constructed by a long-extinct civilization? What had happened to them? Were they turned into zombie pigmen?

“Ever seen these?” Summer raised a coat of diamond armor in one hand, and what looked like a leather saddle in the other.

“I have!” I said, recognizing it as belonging to an animal. “At least the armor. I found that on my island. And I read about the saddle in a guidebook. They’re for horses, right? Or pigs? Have you ever seen a horse or a pig?”

“Both,” said Summer, pocketing the armor, “and donkeys, and even ocelots when I’ve been to the jungle.”

“Have you ever ridden one?” I asked. “A horse? Or even a pig?” My mind filled with images of Summer galloping across the snow astride her trusty war swine.

“Not yet,” she answered, still rummaging through the chest. “Haven’t had the chance.”

“Well, there’ll be plenty of chances,” I said confidently, “when we continue our journey!”

Summer didn’t answer, but instead held up a sword of pure gold. “Here”—she handed me the shining blade—“you should have this.”

“Nice!” Standing back, I gave the blade a few practice swipes. “Thanks!” It wasn’t the sword itself—I could have made a dozen back on my island. But since gold was inferior to diamonds in both luster and strength, I kept the rare yellow metal for other things. It was the excitement of finding it, the idea that these dark, menacing structures could hold pleasant surprises, that grabbed me.

Summer must have sensed my enthusiasm. “Enjoying yourself?”

“You know it! Who knew this place could be so much fun?”

Click-click.

Sounds, farther up the passageway.

Click-shclick.

Bones. Skeletons! I could tag that sound in my sleep. But these were different somehow. Flatter, scraping, as if bones were being dragged across the hard brick floor.

“Wither skeletons,” said Summer, closing the chest.

Shclick-shclick.

“Bring ’em on.” I reached for my diamond sword.

“Mm-mm,” Summer intoned, shaking her head violently. “Trust me, you do NOT want to get close enough to be touched.”

Just then, a figure clacked around the corner.

It looked like a skeleton, but it was black as newly mined coal. And instead of a bow it carried a sword made from common gray stone.

“So that’s a wither skeleton?” I asked.

“In the nonflesh,” Summer replied. Her bow was up, an arrow nocked to shoot. “I’ll do this one.” She loosed a shaft into its midnight skull.

The ebony frame flashed red, hopped back a step, then clacked toward us with stone sword ready.

“Your turn. I’d recommend keeping your distance,” said Summer, stepping aside to let me shoot. But my bow wasn’t ready. I was still armed only with my sword. “Never mind—two more!”

Behind the first skeleton. Summer shot one of them, then shot it again, and a leg bone dropped amid a puff of smoke.

“I got it!” I said. I’d used my sword, but now switched to my bow. I lined up the original skeleton and shot without fully drawing back the string. The result was a hit that probably didn’t do too much damage. But the impact did knock it back. As I lined up to finish it off, Summer loosed three arrows quickly on the third skeleton.

Five arrows hit within four seconds. And all before our attackers could get anywhere near us.

“That’s it?” I said, scooping up the three dropped femurs—or lemurs? Whatever the medical term for leg bones are. “That easy?”

“Unless they touch you,” said Summer, continuing up the empty hall, “and give you a pinch of ‘wither.’ ”

“Can’t be any worse than spider’s poison,” I snorted.

“It is.” Summer’s voice was low, serious, and no doubt packed with memory. “Much worse.”

She didn’t elaborate. I didn’t press. Especially when I saw her pick up her pace. There was another staircase in front of us, and something was glowing up at the top.

Just like the blaze spawner tower, this room was pressed right up against the netherrack ceiling. But instead of a smoldering monster factory, this roof was practically tiled with glowstone!

“Jackpot!” I cried, and turned to my nodding partner.

There must have been at least two dozen blocks, and between the two of us, we hacked and smashed and shattered it all out within minutes.

“So much!” I said, gathering the last pinch of yellow dust. “And all in one place!”

“Quite,” replied Summer with just a tad less enthusiasm. “But the problem with glowstone is that you lose some dust every time you smash one.”

“Yeah, but you gotta admit,” I countered, “that this is still a heck of a…haul.” I yawned the last word, which gave my partner a chance to chuckle.

“You need a rest,” she said sympathetically. “We both do.” She started heading back down the stairs. “Let’s get up to the surface, have a good night’s sleep, and then come right back here tomorrow for another haul.”

“Now yer”—a brief yawn—“talkin’.”

Following her signs, we trotted back down the corridor, past the blocked-up spawner, then down our tower staircase and across the covered soul sand isthmus.

As we ascended the netherrack stairs through the cliff, the ethereal wail of a ghast floated down.

“Don’t,” warned Summer, motioning to my bow, “we’re too hot and tired. Best to just pop into the Ice Cube for a bit, have a water, and cool down, and then if it’s still knocking about we’ll be in much better shape for combat.”

“Makes sense,” I said, trying to stifle another yawn.

And as if it were part of our conversation, the overhead ghast gave another cry. “Brehhh!”

Summer downed a speed potion. “No need to be stingy now.” Then waited for me to do the same.

With me barely a block behind her, we dashed up the remaining steps. There it was: the Ice Cube in front of us, with a screeching ghast behind.

I heard the launch, felt the impact through my feet, the heat at my back. Just a few more steps.

“Brehhh!”

Too slow. No match for adrenaline and bottled speed.

The door behind me. Slamming shut. Cool, refreshing air. The second door. Bright light. Security.

Summer lowered the gravel windows to observe our foiled attacker. It was hovering over the cliff, barely ten yards from our window. But just like so many other mobs, it seemed to lose interest once we were behind glass.

“Good call,” I said, taking a long, quenching gulp of water.

“Mm,” Summer mumbled as she downed her own drink. “Now you see the need for a forward base.”

“You think of…” I mumbled, then yawned “everything,” as all my tension drained away.

How long had it been since we’d slept? A night? Maybe two? I’d forgotten what real sleep deprivation could do to my body, and my mind.

I wasn’t thinking straight. But that’s no excuse for what happened next.

“You know,” I said, reaching into my pack, “who needs to head back up to the surface when we can catch a few z’s right here?”

The bed was in my hand, expanding to a spot on the floor.

Summer raised her hands to stop me. Too late. I started to slide into the bed right as I heard her yell, “NOOOO!”