(Raph, Y/N, Alopex, and Casey were chasing a hooded figure through the sewers.)

(A/N: For the record Riki and Timothy are going to be in less stuff now that they are apart of the Ninja Tribunal. So for the record Timothy asked Alopex to do patrols with the team, so they team doesn't get lopsided.)

"Hurry, Casey, we gotta stop this freak-job!" Raph called back. "Did you see what he tried to do back there?"

Casey shoved past him. "His butt belongs to Casey Jones!"

(The vigilante dropped a couple hockey pucks, shooting them at the figure as it stopped at an intersection. Both pucks hit it in the head and it turned left down a tunnel. Casey continued firing pucks, these ones missing as they rounded a corner. The figure vanished into the shadows of a black tunnel.)

Casey fired a final puck after him. "He's getting away!"

(He skated into the darkness, Raph, Alopex, and Rikiclose behind. Riki squinted into the shadows; he were surely able to see better than others, but even still he was struggling to make anything out with the faint light from the tunnel behind them.)

He heard a grunt as the boys walked into each other. "Casey!"

"Sorry, dude."

(He drew his sword, clutching the hilt  tightly as he made out the form of the hooded figure ahead, eyes glowing ominously in the dark. More eyes appeared behind them and all around the sides of the tunnel, surrounding the four of them.)

"Okay," Alopex said, "evil glowing eyes, never a good sign." The creatures converged on them, bringing them down without much trouble. They managed to get out of the tunnel, though the creatures pursued them. "What are they?"

"Not human," Y/N said.

They got back to their feet, Casey readying his hockey stick. "It's all good, though. We got these punks."

Raph grabbed his shoulder. "Are you crazy? There's too many!"

Casey knocked his hand away. "Casey Jones never runs from a fight!"

(The creatures grabbed his legs, pulling him to the ground and dragging him toward the tunnel.)

"No!"

(Alopex grabbed his hockey stick and Raph and Y/N grabbed on with her, trying to pull him back. More of the creatures dropped down behind the three of them. Y/N gasped as he looked back, ears folding back.)

https://youtu.be/Ulf3l43Ksuw

"Aww, yeah!" Mikey exclaimed, coming into the pit with a box of VHS tapes. "VHS tape mission accomplished! Check it out! I found them in the basement of this video store that went out of business. That last video tape store in the whole city, dude."

Leo started looking through the box and gasped. "Yes! Holy geek-out, wingnut! This is so awesome! Mikey, pizza is on me tonight. Get whatever you want."

Mikey beamed. "Booyakasha-na-na-na-na!" he cheered, dancing.

"Um, what are you fan-boying so hard over, Leo?" April asked.

"Mikey managed to track down all these old super rare VHS tapes of Space Heroes: The Next Generation. The official sequel to the original Space Heroes!" Leo explained.

"These are from the early 90s, but most of the tapes were put in a landfill because the show was deemed too disturbing for kids," Donnie pointed out.

"Seriously? How bad can it get?" Chloe asked.

"Looks like we're about to find out," Ethan muttered as Leo put in the tape.

"Yes! So awesome!" Leo shouted, throwing his hands in the air.

"Eh, it's no Crognard," Mikey commented boredly.

"This is just as lame as the first Space Heroes," Donnie added, looking just as bored.

"Lame? It's making my eyeballs melt with joy! I love this cartoon!" Leo shouted.

Ethan rolled his eyes. "Whatever makes you happy, uncle."

Ethan's ears twitched at groaning from the lair entrance. Turning his head, he saw Casey, Raph, Alopex, and Y/N stumble in, battered and beaten.

"What the heck happened?" April asked as they ran over to help.

"We were on our way back from patrolling the city, when we found this crazy robed cultist-looking guy about to perform what looked like a sacrifice--" Raph started.

Casey cut in. "So, Casey Jones and his team gave chase," he bragged.

"YOUR team?" Raph asked angrily.

"I DON'T work you you!" Alopex exclaimed.

"We tried to corner the robed dude, but he escaped at the last second," Casey finished, ignoring the protest.

"Escaped?" Y/N scoffed, glaring at the vigilante. "Clearly they kicked our butts to Queens, but whatever. There were way more of them than us."

"What the heck were they?" Ethan questioned.

"Human? Robot? Mutant?" Chloe asked.

"Kangaroo men?" Mikey added, putting an arm around Leo, who crossed his arms.

"I don't know, but whatever they were, they were faster and way stronger," Raph answered. "Even by my standards, and that means something.

"Our security sensors have been picking up more homeless people in the sewers. At least, I thought they were homeless people," Donnie mused.

"If these creatures are performing weird sacrifices, then we need to do something about it," Leo ordered.

-x-

"Timothy and I just upgraded these new motion detectors to track down our robed friends," Donnie explained, adding the finishing touches to one. "Now if they're in these sewers within a five mile radius, we'll find them."

Leo took it from him. "Sweet. We split up and put these things within five miles of the lair. Let's do this, team!" he fist-bumped his brother.

(April and Casey took a bag and ran off. Raph, Alopex, and Donnie, followed them, parting off down another tunnel. Leo, Mikey, Chloe, ran off in the opposite direction and Y/N and Ethan took the last bag.)

Just as the two of them were setting up the last of their devices, he heard Ethan's T-Phone going off. "We got movement."

He ran over and picked up his phone from the bag. "It's going off right down that tunnel. Let's go."

"Shouldn't we call the others?"

"We can handle this. Let's move."

"You sure? 'Cause four of them couldn't take these guys."

"We got this kiddo!"

He sighed and ran after him. "If you say so." Ethan could tell that his dad was still trying to prove himself a formidable fighter after losing his arm.

(They rounded the corner and spotted the robed figure walking through the tunnel. The two of them stepped back into the shadows to keep it from noticing them. Once it passed the tunnel, they followed after it, keeping silent.)

(Two more came from opposite sides of the tunnels, following the one they were tracking. The creatures left the sewers and Y/N lifted the manhole cover to see them climbing the side of the building ahead. The creatures entered through the window and Y/N and Ethan got up on top to look through the skylight. There was some odd symbol on the floor with a scroll placed in the center.)

(The creatures gathered around the scroll, picking it up and lifting it into the air, chanting.)

Y/N grabbed his sword and dropped down behind the creatures, pointing his sword at them. Ethan landed beside him. "I believe we'll be taking that scroll now."

(The creatures turned to them, hissing. Ethan swung his shark blade to strike and the creature moved out of the way, making him hit the table. Y/N ran up to punch one, but it caught her fist in its mouth. He struggled to pull it out, only to have drool hanging from it when he did. The creature grabbed him by the face and threw him to the floor, his back hitting a stand. Ethan ran at a creature in front of an impala statue and tried to hit them with his blade, but the creature jumped onto the bookshelves and the impala head came off instead. One of the other creatures grabbed the head and used its horns to pin him to the bookshelves.)

(Y/N used his grappling hook to knock the scroll out of one of the creature's hands, sending it flying out the window. His eyes widened as they immediately jumped out after it. He ran to the window to see them lying motionless on the concrete.)

(He and Ethan exchanged glances as they dropped down to the ground. He bent to pick up the scroll and one of the creature's hands shot out to grab his wrist. The other creatures got to their feet and Y/N and Ethan screamed. They pulled Ethan to the ground and started to drag him into the shadows.)

"No!" Y/N called as they vanished.

(He pulled out his sword and looked around. His ear flicked back at snarling and he spun around as a creature tackled him, kicking it off and jumping back to his feet. The creature came at him again, dodging all of his swings. He spun around as it popped up behind him, bringing down his sword, but it caught it like it was nothing. It slashed at him with its claws, knocking him into the wall. He ducked under its punch and slammed his shoulder into it, knocking it back.)

"Let me go!" He turned to see Ethan on his feet, one of the creatures clinging to his back, reaching for the scroll. "Dad!" He threw him scroll and he caught it, but the creature he'd been fighting tackled him to the ground. The other two creatures dragged Ethan back to the ground and started attacking him.

"Ethan!" The creature on his back pulled his arm back and twisted it, grabbing the scroll. It stepped back and the other two threw Ethan next to him. "You okay, son?" he asked as he pushed herself up.

"Not really," he groaned.

(He looked up at a shadow looming over them to see one of the creatures raising a dumpster over its head. Police sirens sounded from the street, red and blue lights flashing as the car turned into the alley. The creature dropped the dumpster, departing with its companions. Y/N pulled Ethan to his feet, helping him over to the manhole and sliding the cover into place as the police arrived.)

-x-

(Back in the lair, they all gathered in the kitchen and Raph pulled Y/N's twisted arm back into place.)

"They caught my blade in their hands like they were plastic toys," he said, adjusting his shoulder. "It was crazy."

"You should have called us. We could have been back-up, a ninja knows when they're out matched" Alopex pointed out.

"That's what I suggested but someone insisted we would be fine on our own," he argued, shooting a pointed look at his dad.

Y/N looked down in shame as he looked down at his only arm. "I'm sorry, I just-" Y/N couldn't finish the sentence as he gripped his fist with the only arm he had left. Alopex understood and put her hand on his head to comfort him as her tail wrapped around him.

"Guys, listen up!" Donnie called. "This is important. "So the penthouse belongs to a wealthy collector of the weird and obscure, mostly magical stuff."

"Sounds like the perfect candidate for 'I'm the boss of a freaky cult'," Mikey commented.

"Or a circus of weird," Alopex pointed out. "That's coming from someone who was in the circus at one point."

"I think this is the scroll they stole: the Scroll of the Demodragon," Donnie explained.

"A scroll? Like a magic scroll?" Casey asked as April walked over. "Aww, man, I hate magic." 

"Back then I heard tales of the Demodragons. It's an ancient evocation said to summon a powerful monster called Kavaxas. Kavaxas belongs to a mythical race of Demodragons believed to reside in the Netherworld. Magicians are said to summon them for millennia, their efforts always ending in tragedy, but I just thought it was just a fable to teach kids to not poke their heads where they don't belong" Shen explained.

"Sounds like a deal with the devil, if you ask me," Chloe said.

"Eh, sounds like a bunch of nonsense to me," Raph replied.

"Aww, yeah, goul-busting Mikey to the rescue!" Mikey exclaimed.

Raph slapped him. "What'd I tell you about the imagination thing, huh? Focus!" Raph poked him in the head. Mikey slapped his hand away.

"What have you two got?" April asked, standing beside Donnie.

"Well, with the new sensors," Donnie started as Mikey crossed his arms and blew a raspberry at Raph, receiving an eyeroll in response, " I've determined a clear pattern of movement. Right here under the south-east part of Lower Manhattan." A red dot appeared on the screen. "And here and here. But they all converge on what appears to be a dead-end at this one place."

"Hmm, you think this is where they live?" Y/N asked.

"Ooo, if they're actually alive," Mikey said in a spooky voice, wiggling his fingers.

(Leo rolled his eyes and got up from the table, heading to the dojo and standing in front of Splinter's things.)

"Do not be sad, my son."

His ears pricked up at the voice. "Father!" he spun around, his eyes widening as he saw him in front of him.

"Leonardo, I know you feel the weight of leading your family, but remember, I am always with you." He smiled down at him.

"Sensei, we're facing something we've never encountered before, and I can sense something really bad on the horizon. What can I do?"

He placed a hand on his shoulder. "Find the light within. It is the only thing that can save you against these creatures of darkness. These beings are not what they appear to be."

"Then what are they?"

"What are what?" he startled slightly at the voice, turning to see Donnie had entered the dojo without him noticing. "Uh, who you talking to, Leo?"

"It was--" he broke off as he realized Splinter was gone. "...No one. Come on, let's head out."

-x-

(They followed Donnie's directions to the part of the tunnel they'd located, stopping at a dead-end.)

"Hmm. This is the place where they meet up. Doesn't look suspicious," Donnie said.

"Looks can be deceiving," Chloe pointed out.

"I sense something strange close by, but I can't pinpoint it," April said.

"Maybe we should spread out more. Look around," Leo ordered.

Casey looked down a tunnel. "Dudes, we got creepers creeping stage right!"

(They all headed down the tunnel, following three of the creatures into the same place where Mikey had gotten rid of the Squirrelanoids. One of the creatures opened a secret passage on the wall and Leo and the others ran inside after them before it could close, Casey stumbling inside just in time.)

(They headed down a flight of stone stairs, looking around the tunnel. Y/N ears twitched at faint sounds ahead and he held up a hand to signal the others to stop. His ears swiveled toward the sound as it grew louder. He crept up to the edge of and looked down as the others gathered around her.)

(Dozens of the creatures were arrayed in rows at the bottom of stone steps that led up to a strange symbol with a row of lit candles in front of it. The creatures were chanting in that strange language, swaying side-to-side as another cultist ascended the stairs to stand above the others.)

The chanting fell silent as the black-robed cultist turned to face the creatures. "Children. Our time is nigh. We finally have the scroll of the Demodragon in our possession! Now we shall summon a being who will give us all the power we will ever need!" He removed his hood to reveal himself.

"Tigerclaw is the cult leader?!" Leo whispered in surprise.

"Takeshi," Alopex growled.

"Excellent work, my Foot Cultists. You understand the higher truth of our goal. Now I will use the scroll to summon Kavaxas. And with this mystic Seal of the Ancients, I will control him, and be his master." He held up the scroll and a circular stone in his hands.

"Okay, this is not good," Ethan commented.

"We need a plan of attack," Y/N said.

Leo blinked and turned his head to see them all looking at him. "Uh, everyone distract them while Y/N and I get that seal."

"Let's do it. I'm ready." Casey clutched his hockey stick and pulled down his mask.

"Me too." April smiled, nodding at Leo.

"Um, I'm pretty sure these guys are ready too," Mikey said, gesturing behind him. They turned to see a group of creatures coming from the shadows, hissing and growling.

"Aww, sewer pickles..." Raph muttered.

"You couldn't sense them, Red?" Casey asked.

"Their minds aren't like human minds," April said.

(The creatures tackled them, knocking them off the ledge and onto the floor below, restraining them before Tigerclaw.)

"My old enemies," he greeted them. "Perfect timing. Now you can bare witness."

"Takeshi, how's the arm holding up," Alopex sneered as TigerClaw growled at his sister.

"The Foot are finished. Why'd you come back, Tigerclaw? So we can beat you again?" Leo shouted.

"The Foot is by no means finished," he argued. "Look all around you. We have been reborn. After our last battle, the Foot went underground. And in these very sewers, we discovered a strange race of creatures completely dedicated to the Shredder."

"Yeah, well, too bad Shredder's dead," Y/N snapped.

"And who are these freaks?!" Mikey questioned.

"Something you couldn't possibly understand." Tigerclaw smirked. "Make them watch." The creatures forced them all onto their knees.

"Let us go, Tiger Dude! Or I'll knock all nine lives out of you!" Casey threatened.

Tigerclaw ignored him and proceeded to the alter. "You will bare witness to the summoning of a greater being." He stopped at the rising podium. "Kavaxas, the most powerful of all the Demodragons. And his power will soon belong to me."

(Tigerclaw pulled out the scroll and started reciting the spell. As he finished, fire erupted from the summoning circle with enough force to knock back everyone.)

(Leo looked up at the alter to see a dragon-like creature rise up from the ground, maroon wings flaring out wide. It lowered its arms from its chest to its sides and let out a breath of fire before opening its eyes and scanning the room.)

He turned toward Tigerclaw and glared, yellow eyes flashing with anger. "Mortal! You dare call upon Kavaxas?! Lord of the Demodragons, Ruler of the Netherworld?! I will burn you and the rest of these abominations to ash!" He took in a deep breath and roared, breathing fire at Tigerclaw.

Tigerclaw stood and held the seal out in front of him, using it to deflect the flames. He glared at Kavaxas. "You will do nothing but obey me."

Kavaxas held his arm up in front of him in fright before lowering it, staring at Tigerclaw. "Ah! The Seal of the Ancients. You are wiser than I thought, creature. Very well then. What would you have me do, Master?" He bent forward, moving his hand in front of him in a bow.

Tigerclaw laughed evilly. "You will destroy the mutants and their human allies, as a sign of fidelity to the Foot. Make it slow. Make it painful."

"As you command." Kavaxas opened his wings and flew into the air, breathing emerald flames.

Mikey pulled out some pizza from who knows where. "Um, I have some spare pizza here for you," he said nervously. "It's an interdimensional sign of love." Kavaxas burnt it to a crisp. "Man, dragon-dude, you don't have to be such a hot-head."

"Get him!" Leo ordered.

(They all charged and Kavaxas used his fire breath to force them to scatter. Alopex caught his arm with her chain, but Kavaxas smirked as the chain burst into flames. The fire ran down the length of the chain to Alopx's hand, burning her and forcing her to let go. Leo caught her and looked down at her to make sure she was okay before glaring up at the dragon beast.)

Kavaxas's claws began to glow bright and lasers shot out of them, firing everywhere.

"Look out!" Chloe threw up her hands, creating an sheild barrier to shield herself and her team from the lasers. Kavaxas's smirk widened as his lasers hit the creatures as well as the walls and ceiling, causing rubble to fall.

"No, Kavaxas. Attack only the mutants and their allies. You will obey me!" Tigerclaw ordered, holding up the seal.

Kavaxas stopped and turned his head to him. "Yes, Master." He dropped to the ground as Chloe dropped her shield.

(Donnie ran up with his staff raised but Kavaxas threw him aside like it was nothing.)

"Uncle Donnie!" Ethan ran to help him as he dangled off the edge.

(Raph, Y/N, Casey, Chloe, Mikey, and Alopex yelled as all six of them charged at once, but Kavaxas smacked them away without much trouble. He tilted his head as Leo ran on the walls, using the momentum to fly at Kavaxas and bring his swords down on them. Both blades shattered upon impact with Kavaxas's scales. He was slammed to the ground, sliding a little ways past him.)

(Kavaxas stalked toward Ethan, who washelping Donnie up from the edge. Their backs were to him and they didn't see him as he opened his hands, forming a green fireball.)

"Duck!" Chloe and April both ran for them and threw out their hands, creating a shield to protect them, the flames arcing around them instead. When the fire died down, April fell to her knees, panting softly.

"The mortals have gifts," Kavaxas said in surprise. A smirk crossed his face. "And when I eat them whole, I will absorb their powers and use them as I wish." He chuckled darkly, stalking toward them.

Chloe got in front of her friends. "I got a better idea, how about you go back where you came from!" Chloe puts out her hands as her armor forms into a big weapon.

(As the blast died out, Chloe watched as Kavaxas came out with no damage at all.)

"Oh, come on!"

April tried to use her powers against them, but they weren't working. "Why...can't I...move...you?"

"Because I am not of this reality, child!"

(Chloe activated her lightning flashbang and aimed the slick oil at his feet, creating a shockwave and inbalance that managed to knock him back. Smoke exploded in his face as Casey launched a puck bomb at him.)

"We have to retreat! Let's go!" Leo shouted. "Chloe, smoke screen."

(Chloe's mask sent out a wave of smoke at Kavaxas, taking advantage of the temporary blindness to help April to her feet and run for the exit. Kavaxas flew up after them as they ran down the tunnel, breathing fire after them.)

-x-

They stopped in a sewer tunnel, gasping for breath.

"Oh, man. Kavaxas is even tougher than Super Shredder," Donnie said.

"Yeah, at least he didn't have magic," Y/N complained.

"We could barely take down three Cultists. How are we gonna take down an army plus Tigerclaw and Hot Head too?" Ethan asked.

"What now, Leo?" Raph questioned.

"Well, at least we know where their lair is. We just need a new plan of attack," Leo explained. "Donnie, we need an upgrade."

"Can we get our hands on, like, say, two or three dozen tanks?" Casey asked.

Y/N groaned. "Sure, Casey, we'll just infiltrate the military and steal their tanks. I'm sure they'll be cool with that."

"April, is this Kavaxas the new leader of the Foot?" Leo asked.

"I don't think so. I did sense that Tigerclaw summoned him because he's crucial to his plans, whatever they are. That's all I could get."

"I wonder what they're really up to," Ethan questioned aloud.

"Knowing Takeshi...it can't be good," Alopex sighed.

-x-

[Cut to Tiger Claw's robotic hand holding the seal as Tiger Claw speaks with Kavaxas.]

Tiger Claw: :I call upon the power of the Seal of the Ancients to bind you to my purpose.

Kavaxas: By the spirits of all Demodragons past, you have my will.

Tiger Claw: Is it true? Only you have the power to manifest my wish, do you not?

Kavaxas: Indeed, Master Tiger Claw. I have that power and so much more.

Tiger Claw: Then you must do it. No matter what it takes. No matter who stands in your way. You will bring the Shredder back from the dead!

[Tiger Claw raises his hands up in the air, the episode ends with Shredder standing there in the red end screen.]

Hope you enjoyed the chapter!!!