Leonardo and Raphael's footfalls echoed through the sewers of New York as they ran towards the place they were set to meet Donatello and the rest of their family. The two brothers had spent most of their lives in these sewers, and knew them like the backs of their shells. While anyone who came down here would be lost in the infinitely twisted labyrinth of stone, piping, and humid, stale air, the turtles moved through the space like rainwater after a storm. Each turn was made without thinking, each move to a level lower without hesitation.
It was good too, since they were being hunted.
"Any idea where these damn things came from?" Raph looked over at his brother as the two of them lept over a pipe in their way. Behind them, they could hear the tiny, metallic footsteps of their pursuers. While the sewers had seemed to stop them in their tracks for a short while, the robots had seemingly re-calibrated when Raph and Leo met up with one another, restarting the chase. "Don't seem like anything we'd see from the Dragons. Though they're the only ones with reason to send a bunch of murderbots after us!"
"Not important now," Leo responded, motioning towards the subway access hatch directly in front of them. "We get to Donnie, we see what he can do."
"For once having a mega nerd as a brother is gonna come in handy," Raph mused about their situation. "Who woulda guessed!?"
Leo looked over his shoulder for a moment as they approached the panel. What he saw gave him an even higher sense of urgency. A new battalion of the robots flowed forth around the nearest corner like an angry flood of snapping, metal jaws. Whatever had scrambled their circuits down here had clearly been cleared up, and they were back at their full ferocity. They rushed closer and closer as the two turtles unsealed the hatch and slipped in. As Leo closed and sealed the hatch behind him, the metal indented, showing the form of the teeth behind it. The metal seal began to buckle under the repeated blows of the unstopping automatons.
"You know, this reminds me of a Next Generation episode where the Borg-"
Raph cut Leonardo off, "Really? Now? We're gonna do this now?"
"I'm just sayin'," Leo shrugged and smiled sheepishly.
Before Raphael could display any more outward signs of frustration at how much of a geek his brother was, a loud rumble began to approach from down the subway tunnel. The rails nearest tot them vibrated in an unnatural way, and a pair of lights very much unlike anything either of them had ever seen on a subway car. To Leo they almost resembled the shape of the turtles' eyes when they were wearing their ninja masks. Donnie was nothing if not literal when he designed the thing.
The vehicle began to slow as it approached the two brothers, and the large mass of metal came to a sudden stop with a last jolt. Raph and Leo exchanged looks, both of their mouths hanging open in surprise. What stood in front of them was an old New York Subway car that had been completely painted over. Graffiti of the four turtles and Splinter adorned the outside, along with other various tags that Mikey had been trying out.
"We seriously need to sit Mikey down and remind him what 'ninja' means," Leo rubbed his temples as Raph chuckled.
The door to the car hissed open, and Splinter stood in the opening, offering his hands to his sons, "Come, Donatello says we must keep moving or we could be struck by a train."
"Comforting," Raphael sighed as they hopped on.
Before Splinter could close the door, the robots broke through the access panel. The metal door blasted against the side of the transport, and the little metal monsters clambered over one another to get to the mutants. Donatello threw the vehicle into gear, sending the three mutants stumbling to catch their balance. The subway car lurched forward, its wheels searching for a grip. It seemed as if it would never move, before it shot forward like it was launched out of a canon. Not fast enough, as two of the robots lept into the vehicle with them. One was smashed by Mike's weapon, while the other was skewered through its optical panel by Splinter's walking stick.
"Welcome aboard the Shellraiser, dudes!" Michelangelo exclaimed victoriously.
"We haven't agreed on that name!" Donnie called back from the control cabin of the subway car. He made his way back to them, and gingerly took the robot off the rat's staff. "If we have any chance of knocking these things out, I'm gonna need to see how this thing ticks."
"Uh, dude," Mikey threw a thumb over his shoulder at the controls, "who's driving?"
"The computer, of course," Donnie responded absentmindedly as he approached the workbench at the back of the moving train car. Leo looked around, and had to admit that Donnie had done one hell of a job on this thing. The small workbench was located next to Donnie's computer station. There was a small cot with some first aid supplies on the other side, and up front were chairs everyone could strap into if need be. "It runs on an automated program that compiles subway metadata running through the New York Transit system which-"
"Donnie, we talked about this," Leo sighed. "Short, easy to digest sentences."
"It talks to the other trains on the track to know when to turn," Donnie grumbled.
"Wait, didn't two of your test cars crash?" Raph panicked. "Two out of four? As in half?"
"Yea, sure," Don waved his worry away while he started to crack open the robot. "That's why I have a failsafe button. Someone just needs to pay attention and press the red button up front if it blinks."
"Sounds like a job for-" Mikey started.
"No!" everyone else responded in unity.
"Aw," Michelangelo's shoulders fell.
Splinter moved up to the cabin, nodding to the brothers as he did. Leo patted Donnie on the shoulder, "You gonna be able to figure this out, bro?"
The outer shell of the robot cracked open, revealing the complex circuitry inside. Donnie's hands worked like that of a surgeon, pulling out anything and everything he didn't need to do his job. He considered Leo's question, "Yea, but I'm going to need some time."
"Well, lets hope this piece of crap doesn't fall apart on us," Raph looked around at the vibrating train car.
Suddenly a loud thunk emanated from the roof, and Mikey slapped Raph on the shoulder, "Way to be a major jinx, bro."
Leo motioned towards the hatch on the top of the train. Raph and Mike boosted him up, allowing him to flip open the panel. On the other side, the robot was waiting for him. He quickly caught the robot by the neck, and tossed it into the side of the subway tunnel. He watched as it bounced along the concrete and fell to pieces, sparks flying through the darkness. But even as that one was taken care of, multiple new invaders fell from the roof of the tunnel.
He pushed himself onto the roof of the train, rolled, and unsheathed his swords as he came to his feet, slicing two in half as he did so. One fell from above him, and he sliced its head off before it hit the roof of the Shellraiser. Calling down to his brothers, he announced, "Gonna need some help up here! Looks like they're dive bombing us from some maintenance tunnels running above us! You keep working on the drones, Don!"
"Actually they're not drones. More like a cybernetic hive mind that-"
"No one cars, Donnie!" Raphael called down as he joined Leo on the roof. "Just shut 'em down!"
Michelangelo joined his brothers, spinning his nunchaku with vigor, "No joke, I totally had a dream that was just like this. But instead of robots, it was sewer alligators."
"Shut up and smash some robots, you dummy," Raph growled as he plunged his sai through the body of one of the robots. He spun and flung it off his weapon into two other bots, knocking them off the side of the train car. "Man, these tin cans are fun to smash."
The three brothers formed up around the rooftop entry hatch as more and more robots fell onto the vehicle and began to close in. The three of them knew that they had to give Donatello as much time as he needed to do whatever he needed to do. Wave after wave of robots came at them, and the brothers moved as if they were melded with one another. Leo slashed with his swords at ones that attempted to get withing Raphael and Michelangelo's shorter reach. Raphael used his brute strength to tear apart any that got by Leonardo's blades. Michelangelo used his uncharacteristic fighting style to move around the circle in flips and slides, drawing the robots off balance.
But Leo knew it wasn't going to be enough. For every one they struck down, it seemed like four more dropped down onto the Shellraiser's hull. He was getting tired. He figured Raph was as well. Mikey was always enthusiastic in a fight, but he was always sloppy. IF Raphael and Leonardo's proficiently sound fighting slipped, Mikey would get overwhelmed. It wasn't a good situation, and there was a good chance it was going to get worse.
"Uh, bros," Mike sounded worried. "Low bridge coming up fast."
Leo looked over his shoulder and saw that a station was indeed approaching, luckily with no train in it. But it was a low bridge. They wouldn't be able to stay on the roof.
"Father!" Donnie called. "Press the red button! It'll divert us from the station."
"Wait! Don't!" Leo called out to the two members of his family inside the train. "Stay on course!"
"Leo," Raph responded cautiously, "I'm not really keen to be tenderized tonight."
"We won't be," Leo assured him. He kept his eyes on the approaching wall, "Closer...closer...Now! Turtles! Hand six!"
With that, the other two mutants knew exactly where their leader was going with this. The three of them rushed to the back of the Shellraiser, cutting the robots down as they went. When they reached the edge, the slid off the side, grabbing the edge and hanging off the side. The wall ledge smashed into the robots on top of the train, pulverizing them into a blizzard of wires, metal, and circuitry. As the train blasted through the station, Leo almost laughed at the confused humans that watched it fly by in a blur.
"I hope someone throws that up on Tik Tok!" Mikey whooped.
The three pulled themselves back up to the top of the Shellraiser, and their smiles immediately melted away. The robots had already replenished their numbers. The three brothers looked at one another and sighed, readying their weapons.
Before the bots could attack, however, a spasm went through them like a wave. The little metal monstrosities all seized up before falling over, motionless. They all began to slide off the side of the train like penguins on those National Geographic specials Don loved. They all clanged and shattered on the floor of the subway.
"Donnie!?" Leo called down.
"Did they shut down!?" he asked. "I used this one's receiver transmitter to send a simple binary malware that initiated a complete system-"
"Are they gonna turn back on?" Raph cut Donatello off, knowing that he'd go on forever if he let them.
"Not for a while, no," Donnie confirmed. "In the meantime I'm gonna set up a surprise for them if they come into our sewers again."
"Hell of a job, Donnie," Leo smiled.
"Nerd power, bro," Raph agreed.
"Bros, I think this calls for a little deep dish action!" Mikey called out.
"Ugh," Splinter grumbled. "Kids."
The Shellraiser made for the Den, having an adventurous maiden journey. Leo felt pride in his family, but one thing still had him feeling uneasy. Whoever sent these things knew who they were, what they were. They sent incredibly advanced robots after his family, and the turtles had no idea who they were. Their enemies in the city were piling up, and they hadn't even begun to put a dent into any of them.
His family was in danger, and there was nothing that scared Leonardo more than that.