Bad air puffed out of Samazzar’s muzzle as he clambered down the cave wall, a worried frown on his muzzle. The floor of the chamber was covered in scratch marks and the dull red-orange glow from the swarm of cave rats that had stripped it bare last night.

With the millipede encounter still fresh in his mind, Sam had made sure to follow air currents in the dark cavern and find a small and barely accessible crevice up amongst the stalactites and bats. The climb was a bit of a hassle, but looking at the destruction caused by the furry wave of rodents, it had almost certainly saved his life.

His claws clicked onto the stone and Sam grunted under the weight of his pack. Several months of eating well and working out had helped him fill out, but that didn’t change the fact that his build was only slightly more muscular than Takkla’s. He barely stood as tall as Dussok’s shoulder, and not for the first time he silently wished he shared the bigger kobold’s bloodline power as the gear provided by Tazzaera dragged down on him.

Samazzar lowered himself to his scaly knees, touching a claw to one of the red streaks. Distantly he got the impression of body heat, dragging itself across the floor as it scurried toward the cave’s Western exit. With a satisfied nod to himself, Sam stood up and began walking toward the East.

The second level of heat magic wasn’t terribly exciting. Knowing the history of a heat source wouldn’t empower Sam to slay a behemoth or capture a wyvern. Still, a vague memory of a press of warm bodies and the direction they were moving was useful information. Mostly because there were few things more worrying in the deep tunnels than a full swarm of cave rats. Even the millipede would have to retreat before the squealing and biting horde. If Sam ran into them, the rats would strip him to the bone within minutes.

Sam paused in the tunnel entrance. Carefully, he marked down his path through the winding caves on a faded roll of leather. He didn’t really have a destination in mind, content to wander the deep tunnels, scavenging for food until he found the ingredients that Tazzaera needed. Of course, he would need to get home once everything was over.

A smile lit up Sam’s face. He had only left a couple of days ago, and already he missed Takkla and Dussok, but at the same time he was excited to return to the tribe. Half the fun of the adventure would be coming home and comparing what the three of them managed to learn while he was gone.

He set off, barely able to restrain himself from whistling cheerfully as he followed the reddish orange smear of light that marked the path of the cave rats. Although running into the furry terrors wasn’t a good idea, they tended to have set migration routes through larger and more prosperous of the deep caves.

Before long, the sound of the bats rustling on the ceiling faded behind him and Samazzar was alone with his thoughts and the sound of his claws clicking on stone. He kept an eye out for predators or food, but one featureless tunnel blurred into another.

Finally, the faint heat from the rats faded just about the time that Sam came across a small stream, barely ankle deep and burbling with surprisingly warm water running down the center of a passageway that intersected the tunnel he was exploring.

For a moment, he looked forward and to the side, chewing thoughtfully at his lips as he considered his options. With a decisive shrug, he turned and began splashing through the water as he walked upstream.

So long as there wasn’t a clear path, water was as good a bet as any. The deep tunnels didn’t have much to drink, so life tended to congregate around the rare bodies of water. Technically, he could have gone up or downstream. Either direction could easily lead to an underground lake, but the warmth of the water suggested either a hot spring or volcanic activity.

In the tunnels, heat meant life. More than that, both firespores and accordion sponges required hot environments to grow and thrive. Without any leads, his best bet was to follow the tiny creek to its source and hope for the best.

Sam’s stomach gurgled as he walked, drawing a wry expression to his muzzle. He still had a few days worth of smoked rat jerky in his backpack, but he was doing his best to save that. Instead, his last meal had been dinner two days before when he’d been lucky enough to bring down a bat with the weighted net made of reeds that Takkla had pressed into his claws before he left.

He wasn’t nearly as good with the net as Takkla, but with the help of his magically enhanced vision, Samazzar had climbed a wall, sneaking up on one of the giant albino bats that had made its roost perilously close to the edge of the cave. A lucky throw later, the creature was on the ground shrieking in distress, and Sam had his dinner.

Yet another reason to hope for an oasis at the other end of the stream. The odds that Sam could safely hunt anything he came across were vanishingly small. Still, where there was water and heat, there was vegetation. Months of studying Tazzaera’s books left him with an extensive memory of edible plants, fungi and lichens. They might not taste anywhere near as good as meat, but ultimately, food was food.

Sam paused, squinting at the river of orange flowing around his ankles. Distantly, he could feel the vague impression of a large heat source fed by a submerged vent. He closed his eyes, focusing on the second level of his magic, letting it feed information to him.

He could feel the current moving the hot water toward him, splashing and flowing over cold rocks as it tumbled downhill from the spring. Everything outside the creek itself was a grey-blue blur, borderline imperceptible as Samazzar’s will sought to trace the heat back to its source.

One thousand paces? Maybe fifteen hundred? He didn’t even have a proper context for how fast the water was moving. Just that it was and that the current took some time to reach him.

He slipped to the side, leaving the stream to prevent the sound of his splashing claws from alerting a predator as he crept forward. Somewhere ahead, he could barely make out the dull yellow of a massive heat source.

Abruptly, the tunnel ended and Sam found himself in a much larger cavern. Against the far wall, the heat source revealed itself as a large pond, a red shaft of scalding water stabbing from its bottom deep into the rock below.

Sam blinked, letting his magical vision fade as he snuck into the main cave. A forest of bioluminescent mushrooms clustered around the lake, basking in the warmth radiating from its water.

He moved quietly along the far wall glancing at the shoulder high fungus with worry. The heat roiling off of the water would eliminate the advantage of his magical vision. Unlike the cooler tunnels and caverns, the air around the pond practically sang with reds and yellows. Unless a predator was hotter than a bonfire, he likely wouldn’t see it until it was practically on top of him.

Instead, he’d have to rely on the dim blue light given off by the mushrooms and his own jumpy reflexes. Theoretically, there was always the option of simply avoiding the danger presented by the tiny ecosystem, but-

Sam snorted, taking off his backpack and stowing it behind a rock where he’d be able to retrieve it later. Turning down a challenge wasn’t really in his nature. If the first sign of hardship sent him scurrying back to the tribe, tail between his legs, he might as well give up on his dreams right now.

He checked his knife, ensuring that it was tied securely to his thigh via the scrounged scraps of leather he’d dubbed ‘a sheath.’ It wasn’t much more than the stabbing point of one of the cave millipede’s legs, a handle worn into its haft over long hours with a sharpened rock and then wrapped in rat hide to give it a proper grip. Technically, Crone Tazzaera said that the weapon was a stiletto as it didn’t really have a cutting edge, but Sam’s only real concern was that it was sharper and more durable than the stone tools he’d been using to date.

Satisfied, he crept toward the fungal cluster, eyes peeled for predators. It was hard to hear anything over the small waterfall that splashed and burbled hot water from the pond into the stream he’d followed to the cave, but Sam’s ears flicked back and forth nonetheless.

His first stop was at the glowing mushrooms. Sam drew his knife, prodding its pale woody stalk as he inspected the oversized fungus. A moment later, he stood on the tips of his claws, pressing the point of the dagger through its indigo cap. A thick, whitish liquid oozed out of the hole, spawning a triumphant smile on Samazzar’s muzzle.

Carefully, Sam wiped his knife on his loincloth, making sure to clean the grey sludge from its gleaming chitin.

Milklight. A fairly common mushroom in the deep tunnels, it glowed blue to warn herbivores of the poisonous ichor pulsing just under its surface. Luckily for Sam, Milklight’s gills were edible. According to the mushroom’s entry in Crone Tazzaera’s book, scholars debated whether this was an oversight or an evolutionary advantage, like a flower producing pollen to attract bees in an attempt to help the fungus spread the spores buried in its gills.

It didn’t really matter to Sam as he quickly cut squares of the flavorless but nutritious substance from the underside of the Milklight’s cap. So long as he was careful to avoid cutting deeply enough to avoid nicking one of its toxin sacks, the mushroom would provide enough food for days.

He popped a chunk into his muzzle, chewing the spongy flesh of the mushroom as he began moving toward the pond once more, a slight frown on his face. He hadn’t seen any animals in the fungal grove.

Given the Milklight’s glow and relative edibility, the cave should’ve been teeming with small lizards, mammals and insects. Ten or twenty of the mushrooms was enough to support an entire ecosystem, let alone the hundreds that clustered around the hot spring.

That was a bad sign. Samazzar couldn’t put his talon on a specific reason. The water might have toxic minerals dissolved into it. There might be pockets of bad air nearby. The cave rat swarm he’d followed here might have chased them away.

Regardless of cause, it meant that Sam needed to be careful. Even if he had Dussok and Takkla with him, anything that could drive away the scavengers and decomposers of the deep tunnels represented an existential threat. On his own? Sam didn’t like his odds.

Quietly, he popped another square of Milklight gill into his mouth, brushing off his claws as he reactivated his magical vision. A moment of concentration later, he tuned out the omnipresent heat-glow coming from the spring, instead focusing his attention on the presence of good air.

The cave quickly faded into the usual mix, enough good air to sustain life without any of the dead patches Sam had come to associate with pockets of bad air. That didn’t completely rule out poisonous gasses, but at the same time, it calmed some of the jittery kobolds concerns.

He paused. Head whipping toward the pond, Samazzar scurried a couple dozen paces closer, caution disappearing as his eyes widened.

Sam’s tail thwipped excitedly against the cavern floor. Deep in the water, a dozen cylinders of good air clustered around the vent. He couldn’t see that far down, and theoretically there could be a cave network filled with air bubbles, but every instinct in his body screamed that they were accordion sponges.

Finally. He dropped to all fours, scuttling closer to the water’s edge. After days of searching, Sam had finally-

He froze.

Twin streams of bad air bubbled to the surface, originating barely five paces under the pond’s surface.

Hesitantly he raised his head, staring into the lake’s depths. A pair of eyes, each the size of Sam’s forearm stared back at him. Unblinking.

A squeak of protest wrenched itself from Samazzar’s throat as he bolted away. Water sprayed from the pond, drenching him and the fungal grove as the monster leapt from the pond.

Sam’s claws skittered and clattered across the stone as he sprinted toward the tunnel he’d taken into the cave, backpack all but forgotten as heavy footfalls slapped onto the stone behind him.

In ten seconds of frantic running, Samazzar covered the same two hundred paces that had taken him almost a half hour of sneaking. His claws splashed in the stream as Sam exited the cave, barely ahead of his pursuer.

Hot breath tickled his back as whatever it was struggled to force its bulk into the narrow tunnel. Sam didn’t slow down, taking advantage of the creature’s hesitation to open up the gap between them.

He turned a corner, and in the distance the monster huffed angrily at Sam’s escape. It took him another dozen or so steps to realize that it wasn’t pursuing him.

A moment of focus later, Sam reactivated his heat vision. The monster sprang into existence, a squat tailed shape of yellow and orange that clawed unhappily at the mouth of the tunnel before turning around and plodding back toward the pond.

Sam slumped against the wall, breathing heavily as he sought to re-center himself. Finally, a massive smile blossomed on his face.

He stood up and jogged to the mouth of the tunnel, watching his huge, furry adversary as it paused at the lip of the pond, illuminated by the milklight’s glow. It glared back at him for a moment before diving into the water, disappearing beneath the surface with a splash and a wave that soaked the outer edges of the grove.

A purple otter. The toxic omnivores were immune to milklight, living off of the mushrooms in order to render their own flesh inedible to the predators of the deep caves. They were notorious for carrying milklight spores in their fur, setting up new colonies of the fungus wherever they found enough water to support themselves. More than that, they were territorial to a fault, known to accept severe injuries to keep others away from their precious mushroom farms.

A ferocious opponent, but still nothing so fearsome as the tunnel millipede. Now that Sam knew what he was facing, it was simply a matter of developing the right plan and putting it into action.

The otter might be twice his height, and twenty times his weight, but it had something that Sam needed. Rather than a predator to be feared, all he saw as it slipped below the surface was a new winter coat and a pile of merits.