A post popped up in Scholar and Scribe from 
I spotted it when my friend 
Trigger warning - in keeping with the themes of Horror and Desperation that the prompt asks for, this post includes some adult and deeply disturbing content. At least I hope it does. If it doesn't, I haven't done my job properly. You have been warned !
This post is also a sequel to something I wrote a long time ago as a response to a prompt in the Worldbuilding Community.
You can read that original post (which is just as twisted, but without the added nightmare fuel) at Worldbuilding Prompt #282 - The Stone Spiral
Rif's eyes opened. He was flat on his back, and everything hurt. Above him was a black sky with a red overcast. Dead centre, right above his face, almost imperceptible, was a sky blue dot where the sun should have been.
He started to remember. They'd found a spiral of stones embedded in the sand of the beach, right by the sea. Ignoring Miya's warnings, Rif had jumped onto the outermost one and started hopping from stone to stone, working his way in on the spiral to see how far he could get before the stones were too small to bear his weight.
He had got all the way to the centre. The excitement of the challenge had blinded him to questioning what was going on. But hey, he was eleven years old. He was allowed to have a bit of fun !
The last thing he remembered was getting to the centre, making the final leap, and slipping. Hearing Miya's scream as he disappeared into the black hole between the last two stones.
He shivered; cold or uncertainty, he wasn't sure.
"Miya ?"
His voice came out as a whimper. He wanted his sister.
Sitting up, he looked around. He started to feel a sense of deep foreboding. How had he fallen so far and not died ? That circle of sky blue; that must be where he'd fallen from. His world. How could he ever get back ?
He was sitting on sand. Dark reddish-brown, it was a beach that was a mirror of the sunny place he had come from, but this place was dreary, gloomy, cold. The sky was a mass of black roiling clouds with no sign that there was a sun anywhere behind them. Waves crashed onto the beach from a turbulent sea as black as the clouds. Light came from the cliffs, glowing a deep fire red as if concealing lava that was desperate to break out.
In the far distance, he thought he could just see a spiral in the sand. A moment of hope. If he walked over there and circled the spiral, maybe it would take him home ?
Image created by AI in NightCafe Studio
That was when the sand right next to him shifted slightly.
Something burst up from it, making Rif jump. Straight up, stiff as a rod. It looked like a strand of uncooked spaghetti, rigid and yellowish-white in colour. With unnerving speed it jabbed up through the sand and then sank back into it, disappearing between the red grains. But it had been there long enough for Rif to see movement at it's tip. Tiny teeth.
Another one speared up from the beach, jabbing into and through the soft flesh between the finger and thumb of his right hand. Rif screamed in shock and pain as he felt microscopic teeth ripping a passageway through his hand.
Looking down, he saw a drop of blood fall. As it hit the beach, it crystallised and became one with the sand. Red sand. Blood red sand.
How much blood made a beach this big ? How many people had died here ?
Two more strands erupted, close to his legs. He screamed and scrambled away. The next strand came up between his legs, spearing his scrotum as he screamed in horror and agony.
That was when he realised that they weren't just creatures.
They were malice incarnate.
They knew exactly where to strike not just to drain his blood, but to break his mind, to destroy his will.
He jumped up, determined to run for the stone spiral.
Then saw that the whole beach was heaving. These... things.... seemed to live in patches. Dense areas full of the things, fully awake now, jabbing upward over and over at the speed of lightning. But they didn't seem to move, just stab up and down on the spot. He tried not to think of what lay beneath the sand, a churning nest of these things all waiting to sense a victim pass overhead.
He started to run, and the blood-sand in front of him erupted. A strand as thick as his arm pushed up. Slightly slower than the thin ones, but still faster than he'd have been able to avoid it. He could see the teeth in it's tip. They made no sense; concentric circles of overlapping pointed spikes, spinning in contra-rotating rings like a drilling machine. It was only the saliva and blood which told him this was an organic thing, not a machine. As it sank slowly back into the sand, he knew that one this big would do him serious harm.
All he could do was run. Run as hard as he could for the spiral. Avoid the patches where the small ones lived and pray he wouldn't be impaled and eaten by a fat one.
The cold and gloom were forgotten as Rif ran across the beach. One small boy, prey for innumerable monstrosities all trying to spike him from below. He couldn't run straight, he had to watch for the most active areas where the sand was boiling with these horrors.
He fell. The world tilted. Sand flew, and he could taste the iron saltiness of it as it entered his mouth. The beach started to fall away. Rif screamed again, as he finally realised what it was. Another of these things. A word came into his head. "Wormons". That was what they were called, but he didn't know how he knew this.
But this one was no spaghetti-strand, no arm-thick one. It was gigantic, and he was sitting right in it's mouth. A mouth the size of his bedroom, whirring teeth as big as his hand grinding down sand, causing it to funnel like an hourglass with him at the centre.
Scrambling madly, clawing through a blinding dust storm of heaving blood-sand, Rif was pure instinct. He had to get away, get out of this death trap, away from teeth that could shred him in a moment and add his blood to the beach forever.
He didn't know how he did it, but he tumbled out, falling back onto the beach. Right next to it. This one's body was still the colour of straw, but it's surface was rubbery, sickly looking. It reminded him of some kind of giant maggot, but worm-shaped.
He was bought back to reality by another spike of excruciating pain as one of the smallest ones stabbed him between the legs again.
Jumping up, clutching himself in a futile attempt at protection and sobbing with pain, he started to run. The spiral was close, he had to get there !
Trying to dodge the stabbing horrors, he managed to get there. His feet were slick with blood from a dozen pinprick holes, and felt like they were on fire. But he couldn't worry about that. He jumped onto the first stone of the spiral and started to work his way inward.
This time it was not a game. It wasn't an exciting challenge. It was survival. If he had thought it was difficult to get all the way around the spiral on his sunlit beach, this one was a magnitude harder.
He had to keep stopping to wipe his own blood from his feet so they didn't become too slippery. Wormons stabbed up between the stones if he stopped for more than a few seconds. The dim half-light made judging distances hard, and the cold sapped his strength.
Panic and desperation kept him going. Fear of what would happen if he slipped. He was just one little boy, terrified and bloody. He didn't want his blood to become part of the beach. He had to get away from this awful place.
Somehow he made it to the centre. It felt like it took no time. It felt like it took forever. He ached to see the sky blue of home, to see his sister Miya again.
As he jumped down the pit at the centre, he saw the purple of intestines. Not sky blue. He started to scream again as he fell.