There's the unmistakeable sound of a heavy body hitting the floor, the creature letting out another roar. Casey stumbles to his feet, fear for Raphael's life gripping him as he searches for the flashlight.

His head pounds but that doesn't stop him. He can hear the creature's heavy breaths as it sniffs around for him, the cold aura surrounding it making his teeth chatter uncontrollably. It's getting closer, far too close for comfort, and Raphael's silence only serves to make Casey's heart race faster and faster.

He finally fumbles over the smooth handle of the flashlight and he gasps. He grasps it tight and switches it on, aiming it at the creature like a gun, and it hisses at the light again. This time, he can see it in its entirety. She's a lioness, but unlike any lioness he's ever seen before. Her jet-black fur seems to wave as if being blown by a constant wind, black as the dead of night, and her eyes are those same glowing pits of endless white that seem to see right through to Casey's very soul.

She backs up, hissing and spitting as she hunches low to the ground. A low growl sounds from her chest, mouth jittering as she starts to chatter at him, and Casey's skin prickles. He can see Raphael now too, his stomach twisting at the sight. He lays splayed out on the floor, still as a corpse. Four long bleeding stripes mar his shoulder and there are rough scratches on his plastron. The only thing telling Casey that he might be alive is the faint fluttering of his eyelids.

The lioness lets out another low growl and Casey grips the flashlight tighter, the beam quivering, and she shrinks away from it, ears pulled back. Clarity breaks through the panic for just a second as Casey fumbles for his phone, pressing the first speed dial number he can.

It rings and the lioness glares at him and Raphael's chest barely rises.

"Casey?"

Casey almost sobs at the sound of Destiny's voice. "Wolfie! You've gotta hurry! Raph's hurt and there's a freaky lion thing attacking us!" he screams, blood roaring in his ears.

He doesn't hear a response, just a rush of voices before the line goes dead. Destiny is on the move. Casey tries to calm his breathing even as his gaze flickers to Raphael's body again. He has to get to him, but he fears that the second he moves the lioness will attack, and Casey doesn't have a shell protecting the most vital parts of himself.

He can't breathe. Air moves in and out but it does nothing, whistling down his throat and doing nothing to ease the desperation clinging to him like a second skin. He doesn't understand why Raphael is so still. He's bleeding, hurt, but he's seen Raphael take on much worse and keep stubbornly fighting.

"Please, buddy," he whispers. "Please."

His flashlight beam flickers and the lioness lets out a harsh snarl, jolting forward, and Casey's breath hitches as he moves the beam into her path again. She shies away, hissing.

He's losing it. If this light dies, he's dead and Raphael is dead.

"DESTINY!" he screams. "WOLFIE!"

There's a howl from behind the lioness and Destiny, in her wolf form, bursts through the maze of boxes, knocking some aside as she tackles the cat to the ground. The impact sends the both of them rolling away in a mess of black fur, tumbling past Casey and disappearing into the darkness. Casey finally breathes.

He crawls to Raphael's side and hauls him close, gathering him in his arms as he searches for a pulse. He finds it, tiny and thready but still there, but the dread doesn't go away.

"No...no no, not you too, Raph," he begs as he unties his bandana and ties it around the bleeding gashes on Raphael's arm. "Hold on, buddy. Please, I can't lose you too!"

An echoing voice reaches him, far away but getting closer. "Casey!" Michelangelo shouts.

"Casey, Raph, where are you?" Leonardo's voice follows.

"Over here!" Casey cries, his voice breaking with panic. "Hurry! I think Raph's fading!"

The footsteps get closer and Casey keeps clinging to his friend, sparing a glance over his shoulder. The sounds of battle have started to ebb away, but that only serves to stress his already frayed nerves.

Uselessness overwhelms him, utter helplessness threatening to drown him. He can't do anything for Raphael and he can't do anything to fight off the lioness. He keeps waiting for some sign that Destiny is okay, that she isn't going to be another loss that he had a part in causing.

A sharp yowl, distinctly feline, makes him startle and hug Raphael's head to his chest even tighter. He hears more crashing, the sounds of struggle, and then sudden deathly quiet. He gasps for breath, head aching, his heart unable to rest.

"Casey!"

Casey looks up at the turtles as they rush to him. Leonardo drops to his knees beside them, reaching out to grasp Raphael's limp wrist and hold it tight. Michelangelo focuses on Casey, gripping his shoulder.

"Casey, dude, breathe. It's okay, we're here," he murmurs, producing a brown restaurant napkin from his belt. "You're not hurt, are you?"

Casey flinches away as Michelangelo dabs his face. Was he crying? He blinks hard, reaching up to touch his cheek, and his fingertips come away damp. Michelangelo backs up, darting glances at Raphael as he pivots in slow circles, watching every direction around them.

"What happened?" Leonardo asks. He keeps holding Raphael's wrist, fingers pressed to the pulse point. "Des barely answered us before she started running."

Casey opens and closes his mouth a few times, his throat far too tight. "I...it...we were looking at this weird white mutagen and then...then there was a creature—" He winces as a wave of pain rolls over the back of his head. "It attacked Raph and I...I couldn't—"

He grits his teeth against an audible sob. He's shaking so bad his muscles are starting to ache and he's still holding his bandana to Raphael's arm.

"White mutagen?" Michelangelo repeats.

Leonardo rises to his feet, looking out towards the trail of knocked-over boxes and crates that will lead him to Destiny, but he doesn't move. Casey follows his gaze and realizes he can see faint light dancing off the ceiling. The beams get closer, flickering and moving, and Leonardo starts forward while Michelangelo replaces him by Raphael's side.

Sarina emerges from the boxes, her eyes and palms each glowing with blue light, illuminating the bright white of her short hair and jumpsuit and making her seem almost ghostly. Leonardo and Michelangelo visibly relax at the sight of her.

"Sarina..." Leonardo says. "Thank shell."

Sarina nods and turns, lighting the path just as Donatello emerges with Destiny slumped at his side, arm slung over his shoulder and face grave. She can barely lift her feet, sweat making her curls stick to her face. Leonardo hurries to them and Destiny pulls away from Donatello only to stumble into her boyfriend's arms.

"You're freezing," he says the second she touches him, alarm pinching his words.

Casey keeps clinging to Raphael even as he looks back at Destiny. "Did you kill it?" he demands. Her expression pinches. "Des, tell me you killed it."

She lowers her head, shoulders sagging. Sarina moves forward, hands still glowing.

"It seems we were able to scare it off," she says. "The creature was intensely sensitive to light. After a few blasts, it went racing away with its tail between its legs."

Destiny lets out a small growl. "That thing wasn't..." She shakes her head, trying to find the right words. "It wasn't solid. I swear my attacks passed through it sometimes, and it was fast and cold and—"

"You did well," Leonardo assures her, rubbing her arm and trying to bring some warmth back to her. "We have to get Raph back to the lair. We can talk more then."

"Come on, dude," Michelangelo murmurs.

Casey finally relinquishes his death grip, allowing Michelangelo to help him carry Raphael. They lift him, linking their arms behind his back and under his legs.

"Wait," Casey says. He looks back at Sarina and Donatello. "There's white mutagen. Raph and I found it. I bet it's what set your drones off." He looks around, waggling his chin when he finds the puddle again. "Right there!"

"White mutagen?" Sarina echoes.

"That's what I said," Michelangelo says.

Donatello moves to the puddle, frowning even as he produces a small vial from his belt. He stoops, carefully scooping some of the substance into the vial. When it's as full as he can get it, he caps it and tucks it away.

"We'll figure that out once Raph is okay," he says.

"Let's move," Leonardo says.

He slings Destiny's arm over his shoulders, his other arm surrounding her waist as he helps her walk. They make their way back to the beginning and Casey swears he's squeezing the life out of Michelangelo's hands as they work to carry Raphael between them. He can't stop looking down at his friend's pale face.

Hold on, buddy. Please...