www.fimfiction.net/story/48289…
 
Stirring in their seats, with fillies and colts covering their ears to the high-pitched shriek filling the night skies, the many elder equines turned to one another as the cry continued on and on. Finally dying down and leaving the world as it once was. Voices were thrown about, theories and explanations to somehow bring to light an answer to the strange phenomenon. Perhaps it was the train’s brakes, yet they felt no lurch or sudden stop from the locomotive. Maybe an outside force, the sounds of a coming earthquake. But it sounded like no tremor anypony had ever heard before.
 
It sounded louder, stronger, far more powerful. It sounded like the roar of great beast.
 
And to their shock still, a tremor did follow the cry. An earthquake did rip apart the mounds of sand surrounding them. Ponies both young and old that time turned and pressed themselves to the windows, eyes widening in awestruck horror when they witnessed the earthquake in its full, unadulterated, ravaging glory.
 
The earth bounced and rattled, the dirt and sand splitting open to allow bursts of dark liquid to spew forth high into the night sky. Reservoirs beneath the ground erupted as the tremor tore through them, spewing the natural oil out into the open air. And joining the towers of oil were the even mightier towers of flesh and bone. A shell of a leg, bending and rising to allow five others just like it to follow.
 
The jagged, blade-like ends of each leg rose higher and higher, the joints flexing, stretching, to allow the great beast beneath the earth to awaken fully. Outside of the train tracks, just barely missing the escaping train, shrouded in the towers of black oil and raining shards of dirt and earth, all six legs rose to full height.
 
The legs of Scylla sprouted forth from the sands, the creature awakening to answer the call of her new alpha.
 
Reference:  
Titanus Scylla by Pyrus-Leonidas
 
Scylla (c) Legendary