Behind them, something was moving through the room with a noise like sucking mud.

Dean and Emma tumbled down the dark staircase on hands and knees. Fear throbbed in Dean's chest. He strained his eyes to try and see through the black fog that now filled the top of the tower. The noise was getting closer. It stopped, replaced by a high pitched 'tap tap tap' noise that echoed down from the top step. Then a noise like wet laundry plopping onto tiles. Then another 'tap tap tap'.The thing was making its way down the stairs. Dean pulled Emma to her feet and onto the landing below. "The door" she hissed and she pulled from his grasp. Dean heard her fumbling at something and remembered the fire doors, propped open at the bottom of each stairwell. He heard a muffed thump as some latch was undone and a squeal of unoiled hinges as she swung the door closed.

"It doesn't lock!" said Emma, and she grabbed his arm again.

"Let's go!" whispered Dean. 'tap tap tap...splat' there were seventeen steps, it was almost at the bottom.

They felt their way across the floor to the next stair down and descended step by step. The fear of falling balanced by the fear of what followed. The slow tapping became frantic, the thing slopping its way down the stairs at speed now, slamming wetly into the door they had just closed. The hinges squealed again, long and slow, as the door was forced back open and they heard scrabbling as something pulled itself across the landing to the stairway down, faster than before. They unlatched the second door together, pushing it shut behind themselves, then terror drove them down the stairs once again. They were barely slowing it down, gaining a few steps each floor. Panting, sweat stinging their eyes, they descended floor after floor. They were on the third floor when it went silent. This time, in the second after slamming the door shut, they didn't hear the tapping of the thing above them. Dean paused, straining his ears to hear over the banging of his heart. He thought he heard a slithering noise, moving away from the stairwell.

"Did it go back up?" he whispered finally.

"Maybe..." said Emma, "the darkness seems to be fading, a little"

Fuzzy definition was returning to the room. The river of blackness was no longer flowing quite so heavily underneath the closed fire door. There was a table in the corner of the room. Dean grabbed it, dragging it in front of the door. It wasn't as heavy as he would have liked.

"Perhaps its afraid of the light outside." said Emma, "let's get out of here before it starts chasing again."

Dean followed Emma toward the stairs down, placing his hand on the cool concrete wall to support himself while he felt for the first step in the semi-dark. The concrete was vibrating slightly. He pressed his other hand to the wall. The vibration was growing, he could feel it through his feet now, too. Emma looked up at him from half way down the stairs. "What's that?" she said.

They hurried down the stairs, Dean slipping and almost tripping on the last step. He ran straight to the slits in the wall of the second floor. They looked out over the door they had entered the tower by, facing back the way they had come. The light was blinding after the dark of the tower. At first Dean could see only a white glare. He blinked until the view came into focus. Something was advancing across the wastes towards them. A glittering wall, six foot high. As he watched, it impacted a cactus, flattening the plant beneath it in an instant, swallowing it from view. A wall of water, as wide as the horizon, its head muddy and frothing. Behind it the wasteland had become a clear, glittering sea.

"It's a flood..." said Emma faintly, "it's heading for the sea I saw."

"...and all flesh died that moved upon the earth, fowl, cattle and beast, and every creeping thing, and every man" said Dean under his breath.

"I guess I'll be ok, then?" said Emma.

Dean laughed. He fell into a fit of giggles, an uncontrollable, painful laughter that made his stomach sore. Emma was looking at him with worry. He felt self-conscious and the mirth left him "I guess so." he said, wiping his eyes. "I'm sorry, I get like this when I'm nervous."

The water was almost at the tower now, they could see rocks and branches at its head, churned up by the water.

"Do you think the others are ok, in the ruins?" said Emma.

Dean shook his head, "I don't know. I hope so. I guess we're lucky this tower was here. It looks like we should be well above the water level. We can just wait it out—"

He saw it out of the corner of his eye. A twitch of movement. Something in the corner of the room, against the ceiling. He stepped back as he turned, stumbling against Emma who grabbed him, stopping him from falling. "What's wrong" she said, then her eyes followed his. It had stuffed itself into the corner, squishing its oily black body into the angle. The size of a cow. Its head was invisible, still surrounded by a thick cloud of fog. It had stopped producing the blackness, lulling them into a false sense of security as it slipped out of the tower, climbed down the outside and entered from the front door. Dean could make out four thin scaly legs jammed awkwardly against the wall, each ending in two yellowed claws. The movement he had seen was from its feelers. Long and thin, they waved from where its head must be, protruding from the black fog, searching for something.

"I don't think it can see" whispered Trix, and the feelers darted in her direction. "I think it was tapping to find its way around, and it can't see us, but it can hear us."

"What's it waiting for?" said Dean through gritted teeth, his back up against the wall of the tower.

The tower shuddered as the water impacted the side of the tower, Dean looked outside and saw the waters throthing as they parted around the tower, flooding in through the front door and filling the bottom floor. There was a wet sound of releasing suction and a heavy thunk. He spun back around to see the thing drop to the floor. It was facing them now, its feelers waving in their direction, stretched out as far as they could go. Triumphant. It's front claws felt carefully at the floor ahead of itself as it tapped its way toward them. No longer hurrying. It's prey trapped.

Dean didn't know what to do. He thought of the door up, the way blocked by a table, then topping out with that huge drop. He imagined them being pushed ever back, retreating onto the walkway, then holding hands and flinging themselves off, the wind whistling in their ears as they fell. He thought of the stairs down, the dark water waiting on the first floor, felt it filling their lungs and draining the warmth from their bodies, the creature fishing their lifeless bodies from where they floated. He stared at the horror in front of him, unable to look away. What was it hiding behind that cloud of darkness? What form of mouth was in that blind, eyeless face. Would it bite, or suck, or tear?

He didn't have time to decide, Emma was pulling him toward 'death by drowning'. She put a finger to her lips and they crept along the wall, out of the path of the monster. It stopped, its feelers waving randomly, then its face turned the way they were going. Oh, no. thought Dean, then it launched itself at them, its back feet skittering on the concrete as it covered the distance in a few short bursts. Emma and Dean fell to the side and the creature smacked into the wall, throwing off a splatter of black oily liquid that covered their arms and face. It stank of stagnant water and rotting fruit. They clambered for the stairwell on their hands and knees, the oily liquid making them slip, and tumbled down the stairs.

The floor below was already filling with ankle height water. They ran into the room, their fleet splashing loudly. The creature fell down the stairs behind them. It squealed furiously, a sound like ten piglets in a burning bag. It leapt at them again, its back feet overtaking its front as it struggled to find purchase on the wet floor. It slid across the room sideways and collided with the opposite wall, giving them a brief opening to reach the stairs that lead to the fully flooded first floor.

"We have to swim!" screamed Emma, and they rushed across the room before the beast could get to its feet. Emma waded down into the black water of the final staircase down. Dean followed her a few steps back. The water was up to his thighs, it felt warm. He tried to remember what the way out looked like: the path he would need to take to reach safety, air, light. Panic overtook him again as he imagined that journey, swimming through the pitch black water, the concrete ceiling above him, blocking access to air, the creature just behind. He was hyperventilating. Emma took a deep breath and slipped into the water, disappearing into the darkness. He turned and saw the creature on its belly now, propelling itself across the wet floor. It flicked its head towards him and for a second the mist didn't keep up. He saw many mouths, wet and sucking, dripping with black ichor. He threw himself into the water.

His eyes were open but could see nothing. He hoped that the faint glow ahead was the door. He swam toward it, tearing at the water with his open hands, kicking desperately, the vision of those mouths seared into his mind. His slowly depleted breath began to feel stale, it grew painful in his lungs, as though it was turning to poison the longer he held it inside. He let some out, feeling the bubbles rushing up past his face. He was almost at the glow, he could see the outline of the door. Just a few more seconds— something grabbed hold of his foot, a soft, warm thing closed around his ankle. He kicked backwards desperately and the rest of the air in his lungs fled out in a huge cloud of bubbles. The thing on his leg was pulling him back into the room, climbing up his leg with rythmic contractions. Swallowing him. He kicked again and again with his other foot, the water sapping all the power from his strike. He slammed his heel into the soft, giving flesh of what must be of the creature's mouths. He felt it retract slightly, and managed to wrench his leg away just enough to get a grip on the door frame. He pulled himself forward, his heart hammering in his chest, his lungs shooting with pain, his vision narrowing to a point -- he felt a terrible pain at his ankle, then his shoe slipped off and his leg slipped free.

He popped to the surface and sucked in air. Filled his lungs. The water below was still opaque, and he thrashed his legs, kicking madly down. His left leg felt hot and numb where the thing had grabbed him. He expected the monster to rise up next to him any second, drag him back down into that cursed tower. He saw Emma bobbing just ahead of him and tried to shout out, but a wave caught him in the face and he only managed to splutter. The current grabbed them, rushing them around the tower and away, away from the creature, away from Trix and Wilbur and the ruins, toward the sea.

He bobbed in the water, struggling to keep his face above water, twisting left and right to look for the creature, to keep Emma in his sight, he saw her head not far away and struck out in her direction, scared he would lose her in the endless waters. He felt faint. In the back of the mind he remembered that first day in hell, the poem Salome had recited.

The hellish trees, the slimy seas,

The city hewn from silver stone,