Casey stumbles into the lair late the next morning, his skin paler than usual and dark circles appearing under his eyes. He yawns, clipping the pinball machine with his shoulder. He winces, grasping the aching limb as he moves further in.
Leonardo sits on the couch, his eyes shut and his legs crossed in front of him. He breathes evenly, seeming not to notice the arrival of his tall friend. Casey can hear chatter in the kitchen, wondering how Leo can possibly try to mediate out in the open like this.
"Hey Casey," the turtle greets rather suddenly, causing the said boy to jump. His sapphire eyes open and flicker to his friend. "Sleep well?"
"Maybe?" Casey mumbles. "I feel like I was run over by a truck."
He grits his teeth as he rests his hand over his heart, taking a few deep breaths. Leo eyes him skeptically and gets to his feet, dropping the look and smiling a tiny bit.
"Well, there's still some breakfast in the kitchen if you need," he offers, gesturing to the nearby room. "Mikey made these new omelettes that are...actually amazing." He shrugs, looking pleasantly surprised.
"Yeah...sure," Casey says, not liking the burning pain spreading through his entire chest. He sucks it up, walking towards the kitchen as he tries to act like nothing is wrong.
He finds the rest of the Hamatos crowded around the table, eating and laughing as they celebrate being free from another villain. Michelangelo chucks little cubes of cheese across the table, letting Raphael catch them in his mouth. Donatello shoves his hotheaded brother subtly every now and then, just enough to swoop in and snatch the dairy product out of the air first. Sarina laughs at their antics, Destiny making more food near the stove while Annalise cleans the messy workstation.
"Yo Casey! How much you wanna bet I can catch two at once?" Raph calls upon noticing his friend.
The teen shrugs, his head starting to spin and the burning pain making his entire upper body feel numb. He slides into the nearest chair, rubbing his eyes and trying to get a grip.
"You okay there?" Destiny wonders, setting an omelette down in front of Sarina.
"Nothing, just a headache," Casey mumbles, his vision starting to become unfocused.
"Do you need some food? Bro, we can hook you up!" Mikey says, accidentally hitting Donnie in the eye with a cheese cube. "These omelettes are literally the best thing I have ever created!"
"Right next to pizza puffs," Annalise adds, snagging some cheese from over her boyfriend's shoulder and popping it into her mouth.
"Any luck with that mutagen?" Casey asks, trying to divert the attention from him.
"We can find no plausible use for it, so we locked it up to deal with at a later time," Donnie answers, rapidly blinking the one eye that got hit.
"So you aren't even trying to make retro-mutagen?" the vigilante snaps as his head shoots up, instantly making him regret the movement as his entire body grows more weighted.
"We told you, Casey," Sarina says, her face straight and emotionless. "Destroy that one vial and we're toast. No more. We have to find another option."
"You just said that you weren't finding any uses for it!" he says, his breaths slowing as his chest heaves. "What use are those big brains of yours if you don't use it to help people?"
No one responds, every pair of eyes on the teen. His face blazes with heat as he gets to his feet, instantly wobbling and having to grip the table again, his limbs shuddering.
"Dude...what's up with you?" Raph asks, visible concern on his red-masked face.
"N-Nothing! I'm fine!" Casey insists, blinking rapidly as he exhales, the sound audible to everyone in the kitchen.
Leo appears at the kitchen entrance, confusion evident in his entire persona. Destiny turns off the element and puts down her spatula as she turns around, her body completely turned to Casey.
"Now, that's just a lie," Donnie says. "Something is wrong. What aren't you telling us?"
"I told you! Nothing!" Casey repeats, pushing off the table and turning around.
His legs buckle beneath him, instantly pitching him forwards. Leo reacts in a snap, catching him as his body sags against the shorter boy's. Raph launches to his feet as Destiny brushes past everyone in a blink, next to her boyfriend and best friend within a second or two.
"Casey? Casey, talk to us," Raph demands, joining his other two family members.
Leo shifts Casey's limp form, carefully lowering the both of them to the floor. The others lean closer, their eyes wide with shock at the turn of events. Destiny's ears flatten as her wings tighten against her back, leaning closer to Casey as she sniffs a little. Her stomach twists.
"No...no way," she mutters.
"What is it, Des?" Donnie asks.
Destiny blinks a few times as her nose wrinkles. "I...I'm smelling something weird on him. Like...rotten ice, if that's even a thing."
"Rotten ice?" Mikey echoes. "That sounds weird, dudes."
"Des, Raph, watch him. I'm getting Splinter," Leo says, scooting out from underneath Casey's head and hurrying from the room.
Raph kneels and takes charge, turning his friend's head as he checks for a pulse. Destiny sniffs again, looking more and more put off by the second.
"Perhaps you're smelling some sort of infection," Sarina comments. "Dogs and other animals have shown to be able to detect diseases in humans much faster than medical personnel can."
That makes the wolf-raven tense even further as her wild green eyes widen. "Raph, get his shirt off."
The red-masked turtle's face flickers with absolute confusion. "Uh..."
"Oh don't even start. Just do it," she snaps, giving him her best glare.
He nods, Donnie getting up and helping his brother. They pull the boy's sweater and shirt off, instantly making everyone's stomach drop. There's a deep purplish gash crossing from his shoulder down to below his left pectoral, dried blood festering along the edges and veins of the same violet hue spreading out from the spot.
"Oh no..." Sarina squeaks, covering her mouth with her hands.
"What? What is that?" Annalise demands, her blue eyes going wider by the second.
"To be brief...he's been shaded," Donnie says thickly. "And it's infected." Casey groans, his eyes opening a crack. Everyone jumps at the movement, Donnie leaning close to his friend. "Casey, when did this happen?"
He blinks, his eyes starting to glaze over. "The fight...Beast Mode got me..." He coughs, the sound ragged. "Didn't think...it was...big deal..."
"Not a big deal?!" Raph exclaims. "How could you-"
"Raphael, think before you speak," Master Splinter interrupts as he appears with Leo at his side. The rat's russet eyes widen when he takes in Casey's wound. "Casey...what has happened to him?"
"The same thing that hurt Raph got him, except he didn't tell anyone about it," Sarina explains, her usually collected tone wavering. "With Raph, we got Zilla to heal him before the infection spread. Since Casey didn't tell us-"
"But Raph went way longer before it got infected, Sarina," Leo interrupts. "So how could Casey's get this bad this fast?"
"Theories are as follows," the cyborg says. "One, because with Raph the wounds were different, as though Beast Mode used a different sort of attack on him. Two, because we cleaned Raph's wound within an hour of infliction and he got a solid amount of rest afterwards that helped slow any infectious bodies from growing." She massages her temples as her eyes flash. "Casey not only stayed awake for long after the battle, but didn't get any help in cleaning his wound. There was also no blood to suggest that he was ever-"
"Okay! We get it, he's hurt! We've got to get him to the hospital!" Raph shouts. "Maybe they can help him!"
"I doubt it. This sort of wound is-" Donnie starts.
"Raphael is right. We must bring Casey to trained professionals while we search for other options," Splinter interrupts. "Donatello and Sarina, please retrieve human patches for all who need it and medical supplies to help slow whatever infection is currently spreading. Leonardo, call April and let her know what has happened. Annalise, you must contact Casey's sister. Raphael, you call Taylor." The rat's ears flatten as he looks to the remaining two children. "Destiny, Michelangelo, we will take Casey to the ShellRaiser and make him as comfortable as possible."
"Hai Sensei," everyone says, getting to their feet and scattering.
----------
"Look, Tay, I'm not saying come out here," Raphael says into his t-phone. "You've got school. Don't-"
"Hell no. If Casey is hurt this badly, I'm coming," Taylor interrupts. "You already made me stay put when it was you. I'll drive out as soon as I can."
Before he can argue, the phone line goes dead. He sighs and puts his phone away, looking up at his family. Donatello talks to one of the receptionists at the front desk, Destiny and Sarina sitting with Annalise, Casey cradled in their laps. Leonardo and Michelangelo stand side-by-side near their brother, once in a while fidgeting with their human clothes.
The receptionist nods and turns to call the nurses, causing Donnie to turn and move back to his worried family.
"They got him a room and are scheduling for the doctor to come see him," he announces, tousling his shaggy brown hair as he adjusts his glasses. "So...now there's one more thing to do."
"Which is?" Leo asks.
"We have to tell Zilla what happened," the disguised turtle continues.
"I'll do it," Mikey volunteers instantly. "I'll tell her whatever you need."
Annalise swallows the lump growing in her throat, standing up. "I'll go with you, Mikey. Two heads are better than one."
Donnie sighs. "Okay...but you have to tell her exactly what I tell you."
They both nod in response.
----------
"SHADOW! ZILLA!" Michelangelo hollers as both him and Annalise head down the streets. "ZIIILLLAAAA!"
"Mikey, please quiet down," Annalise begs softly. "You can't bring attention to yourself like this."
He frowns as he turns to her, his baby blue eyes drowned with sadness. "How else can we find her? Casey's gonna die if we don't!"
The blonde sighs, brushing her hair out of her eyes. "Well, it's the daytime. She's going to be hiding in alleyways."
His face goes blank. "Oh...right."
The pair slips into the nearest alley, continuing their search. It isn't until quite a bit later that their pleas are answered.
"Mikey? Annalise?" Zilla asks, slipping out from beneath a dumpster. "You're honestly the last people I expected to see." Her face flickers with confusion as she takes in the humanized Mikey. "Wait...but you look different."
"Human patches, but that's not important. Casey got shaded, bro!" Mikey says, his tone thick with anxiety. "Donnie thinks it's gotta be you who makes the big tough decisions."
Zilla's expression floods with fear. "Casey got shaded? But...that isn't..." She stops as she narrows her eyes. "Beast Mode..."
"Donnie said that there's three possible options," Annalise adds. "Either we can let him slip away, you can try and heal him, or..."
"You can mutate him into a shadow mutant like you!" Mikey pipes up. "Using that last little vial of retro-mutagen and stuff that we have in the lair!"
The shadow remains completely still, her arms pressed against her sides. "Mutate him...into someone like me?"
"Donnie and Sarina both said it was an option," Annalise whispers.
Zilla looks down, her shoulders slumping. "If this wound is infected, I can't heal him, and there's no way I'm letting him die." Her breath hitches as she hugs herself. "I'll go to the lair and get the mutagen. I'll come to the hospital as soon as I possibly can." She looks up at them with a serious glare. "Don't tell anyone else what I'm going to do. Got it?"
"Got it," the couple choruses.
They turn on their heels and head back to the hospital, leaving the shadow to mull over their words.