Zombie Apocalypse: Rising Heat

The amount of brush in the area had to have been huge to leave this much ash and soot. Even after the heavy rain that swept the area, the smell of charred wood still permeated everything in the sizable clearing. The wind carried bits of ash as it blew toward him off of what his experienced eye told him were the remains of improvised structures near the middle. That broken circle of rocks nearby was probably a fire pit used for cooking. What was left of that contraption hanging from the trees was a mystery though. Some manner of defense, most likely, but not enough of it left to tell what kind it may have been.
But the most baffling thing was the pile of bodies. Well, bones anyway. The rest was just shriveled tissue and a glaze of melted fat. Despite the large open space, all of them were up against a rock sticking out of the side of the hill. Didn't seem to be anything on top of the hill to draw them, and they would probably have just gone around anyway. It wasn't exactly hard to get up there.

"Why would they do that?" he wondered aloud.
"Huddling away from the fire. I can only imagine how horrible it would be. Surviving the nightmare that the world's become only to die like this? It's...just wrong." Her voice broke a bit at the end which prompted him to look up at her. Green eyes close to tears stared out from underneath her reddish brown hair at the mess before her. Rising from where he was crouching, he briefly patted her on the shoulder. Good girl. Strong. Just cared too much sometimes.
"I wouldn't feel too bad about it, Val. Those weren't survivors."  Her eyes widened in surprise. "Look at the ground. What's missing? What would survivors have that's not there?" A couple minutes passed with her pacing back and forth examining the ground, the near tears of a minute before now replaced with an analytical eye. Finally stepping back beside him, she still stared at the ground as though looking.
"Weapons?"
"Right on the first guess. Even if they didn't all have guns, they still would have had something to defend themselves with. Blades, crowbars, ax heads, hammers. None of that would succumb to this much heat. " He gave her a small smile of encouragement. "So the question becomes..."
"What would zombies find so important about that rock?" she finished after a moment.
"Right again."
"Well, if you want to know, then just take a look." The low voice of the man with a mohawk came to them as its owner strode across the field. Always a blunt one, aren't you, Wadey? The big guy headed straight for the rock, seemingly unconcerned by the crunching and squelching of bone and ruined flesh beneath his boots. Val looked ill. Leaving Wadey to his grim inspection, he turned back the way he had come from.

"Find anything?" That was addressed to Swift. Perhaps the most nondescript man he had ever seen, he thought it might be impossible to pick him out of a crowd. He seemed to have no outstanding features whatsoever. An average face on a body with an average build. So overwhelmingly ordinary that he seemed to almost disappear whenever he stood next to other people. Frankly it was a little disturbing. Still, it was good to have him around.

"Not much. The only used trail is the one we followed up here, and you already know that someone's been along it since the rain. Yesterday at latest, you said. You find anything here, Watch?" Rrwatch, he corrected silently, and let it pass. It wasn't important, and a man of his age had learned not to waste energy on pointless squabbles.
"Little more than we already knew. Definitely a zombie attack, though no saying what flavor with everything here reduced to muck. There must be close to 40 of them piled around that rock, with I don't know how many more outside that ring of heavy ash. It was a heck of a fight, I'm thinking.
"This camp's been up and going for a long while. At least a few months. Thinking at least 5 occupants. Those who came here yesterday didn't stay long. Just surveyed the place quickly and turned right around and left. Either they knew there was nothing to loot, or they had some place else to be in a hurry. Weird thing is that rock over there."

There was a loud thud from the direction of the rock in question. Wadey had thrown himself against it, it would seem.

"I think it moved." said Val. They all shared a look. Without another word, Swift went to join Wadey by the rock, though he hedged around the outside of the mess and picked his way through instead of just trampling on it. The two younger men set their feet as best they could and heaved. The rock did indeed move. Backwards into the hillside perhaps an inch or two. Nothing seemed to have shifted in the rock face above, so apparently it was safe. They heaved once more, this time getting more than a foot of the way in. A faintly musty scent crept out of the new hole and mingled with the ash. The air inside was going bad, but only just starting. Cave must have been open until recently. One last heave and it slid in all the way.
"I need light," rumbled Wadey, drawing one of the hand axes he kept on his belt and holding out his other hand for a flashlight. Swift pulled his pack open and retrieved two from it, handing one over.
Rrwatch shrugged at Val--Nothing for it but to follow.--and readied his rifle. She took the cue and unholstered her own handgun.

The inside of the cave was cool and smelled of water, a welcome change from the burnt gore and ruin above. A faint rushing sound in the distance meant the possibility of an underground stream. Rrwatch took the lead, scanning the cave floor while the others watched ahead.
"Hold up. Tracks."
There in the dust was a clear boot print. Another nearby, a different size. And there, an animal track. Dog of some kind. No telling how old these were, but he'd be willing to bet it was no more than a handful of days. The night they'd seen the fire and decided to come to investigate.
Turning the corner brought a sudden increase in the sound of water. A little light showed a strong stream of water bursting out of the wall along the right of the path and falling down into what appeared to be a lake. Carefully making their way down confirmed it. A sizable cavern with an underground lake spread before them.

"It's a shame what happened to the place," Val said. "Good location, natural spring water from in here, easy hunting area."
"Is that a tunnel out there?" Wadey pointed toward the far wall of the cavern. Swift added his light to Wadey's.
"Looks like it."
"What's that noise?"
"What noise, Watch?"
"It's like a wooden thumping. Like something hitting a log." They shined their lights around the nearby shore. "There." Not far away was a piece of wood caught on a protruding bit of cave wall in the water, the waves batting it against the side repeatedly.
"Just some wood." said Wadey dismissively.
"Look closer. It's been worked into a rough paddle shape. They most likely had a canoe or boat down here."
"Brilliant! All that other stuff, and a shelter with an escape route. This place is gold! Give me some light here. I wanna check the map." Val pulled the weathered map from her backpack and carefully unrolled it. The film advertised on the outside had long since missed its showing, but the back of the poster had found new life as pretty durable map. They'd put it through the mill though. It would need to be copied soon. After a minute's inspection, she announced confidently, "I'm almost certain this lets out the cave at Label Lake. If they took a boat down it, and it didn't branch off somewhere else too, then they would be just outside the city when they came out."
"That's a pretty big if, but I think it's worth a look. What about you two? Up for a bit more tracking?"
"You're the boss." came the rumble. Swift contented himself with a nod, barely visible in the light.
"There's no other boat or we'd be able to follow them easy enough. We've got time. Let's get back to town and set up for the night."

A couple hours later they were walking down the deserted city streets. The afternoon heat pressed down on them, making each step more of an effort than it had any right to be. Strange how they hadn't seen any zombies. There was almost always a few that needed put down, but not a single one was to be found today. Come to think of it, the earlier trip in the morning had been just as uneventful. He wanted to believe it was a sign of things getting better. So, why was worry creeping along next to him like an itch between his shoulder blades? The empty windows of homes and businesses so long left untended seemed like hollow, sunken eyes watching their procession silently. As the sun began to sink lower in the sky they started searching for a place to take for the night, settling at last on a nearby bar.
The side window was broken, but that seemed the only visible weak point, easily blocked off. Inside held its own surprise though. Dust and rotted bits of cloth marked the resting place of at least four Shamblers. Someone had fought here a while back. Well, if it had been assailed, then maybe it wasn't the best spot.

Taking some of the liquor left inside, they made their way across the street to a nearby apartment building and onto the roof through the fire escape, pulling it up behind them and blocking off the roof access door. They were just settling in when the wind shifted and brought them a horrific stench that left them choking and coughing as quietly as they could manage.Thankfully the wind shifted again shortly after, but no one was eager for their meal anymore. In fact, Swift decided to empty his stomach over the side of the building.
"What is that?" he asked, pointing off down the street a couple blocks away.
"Where?"
"There. In front of that firehouse. Looks like a big mound of flesh. You think that's what's causing that smell?" The wind chose that moment to change again, most definitely coming from that direction, and sending them scrambling to cover their noses and Swift into dry heaves.
"Let's get inside. It's dangerous, but we can't stay out here. We can do something about that thing tomorrow."
"You're the boss, Watch."
They went to unbar the door inside, but a slight tremor running though the ground brought them up short. Looking out in the failing light they could just barely see it.
The mound was moving.