*Disclaimer: I do not own the rights to the Teenage Mutant Ninja Turtles franchise.

*Author's Notes: Well, the new year is here and so is a new chapter of 'Slash's Revenge.'

I want to take a moment to thank everyone for the overwhelming number of favorites, follows, likes, reblogs, reviews, and/or comments on this story. You're all so incredibly kind. Thank you, thank you, THANK YOU! C=

I also want to take a moment to thank my creative consultant/beta reader, Joanne N. Grey. She's one of my very favorite people on the planet and I simply adore her. Thank you from the bottom of my heart, Joanne.

Okay, let's get on with the chapter... ;) CJ

Chapter 4 - Slashback

The temperature outside had dropped significantly from the previous night. This served as a rather apropos metaphor given what had happened back at the lair to make Donatello flee to the surface that he was now sitting high above.

Using the silhouettes cast along the rooftops to conceal himself from the humans below, the purple-masked turtle peered down at the streets of New York City.

Aside from the traffic whizzing by well beyond the posted speed limit and the occasional colorfully outspoken pedestrian strolling along, it was a fairly quiet night. Of course, Donatello's idea of a quiet night was probably a lot different than what most people across the globe considered quiet. After all, he and his brothers spent the majority of their evenings either fighting off the Kraang or going head-to-head against the Shredder and his evil cohorts. Saving the world and taking down the bad guys was noisy business. Plus, the brothers had to do these things with Mikey at their sides and it was no great secret that the youngest turtle was typically louder than all of their foes combined. Always trying to 'chuk' every enemy in sight and constantly calling out his self-coined battle cry, 'Booyakasha!'

Dumbest. Word. Ever.

The worst thing was, Michelangelo used that stupid, made-up word so much, all the brothers were now guilty of blurting it out every now and then. Even the ever-serious Hamato Leonardo.

Whenever Donatello found himself unintentionally spouting off the ridiculous word, he could almost feel his IQ dropping by several points.

Hanging out with Mikey could definitely be taxing on the brain cells, as well as the nerves. Still, without the little jokester around, things sometimes tended to get a bit boring. Kind of like they were right now…

The highlight of Donnie's night out on the town so far had been witnessing a couple of gray squirrels duking it out over what looked to be a discarded lollipop. The grueling, ten-round boxing match had come to an abrupt end when a rather mangy-looking dog came by and chased the rodents off before either one of them could be declared the actual winner or claim what was left of the half-eaten sucker.

The genius turtle was pretty sure his younger brother would have found the no holds barred squirrel fight extremely entertaining. Although, ever since they had come across those freaky 'Squirrelanoids' a while back, Mikey seemed to be a little skittish around most small, woodland creatures. Just like Raph got whenever he saw a cockroach.

Raph…

Donnie had been trying his best to avoid thinking of his hotheaded brother, because every time he did, it just made his heart sink even further.

Heaving out a dejected sigh, the turtle in purple sealed his eyes shut. He then began to inhale and exhale at a deliberately slower pace; the way Master Splinter had taught him to do during meditation practice. Listening to the calming sounds of vehicles rushing by below him, Donatello attempted to focus on the soft sensation of his mask tails brushing up against his skin while they flapped lazily about in the cool evening breeze. He breathed in and out through his nose, as deeply as he could, trying to quiet his thoughts and find his center.

But alas, meditation had never been one of Donatello's strong points, much to his father's continued frustration. Maybe that was because asking the intellectual turtle to clear his mind was sort of like asking Mikey to sit still.

Not going to happen.

Awww, yet another thing that I totally suck at…

Keeping his eyes tightly screwed shut, Donatello once again attempted to harness his chi, but his efforts were ultimately wasted. The painful memory of what had transpired back at the lair made it impossible for him to achieve any kind of inner peace. All he could think about was what Raphael had said to make him run off…

"I don't want to hear it anymore! You're always screwing everything up, Donnie! How many times have you nearly killed us now? How many times, huh?"

The unkind remarks caused the night air to feel that much colder against the brainy turtle's already chilled skin.

Prying his eyelids apart, Donatello shook his head from side to side, hoping the movement might help shake Raphael's harsh words out of his thoughts.

No such luck…

One of the downsides of being overly intelligent was that Donatello's mind tended to work like a sponge, retaining every little thing that he read, heard, and saw. While this could oftentimes be considered a blessing, there were plenty of times it could also be considered a curse. Especially those times when someone said something cruel to him. It was hard to forgive and forget when your photographic memory simply refused to let things go.

Of course, the fact that Donnie was presently sitting on the edge of the very same rooftop that they had been on when Raphael had finally managed to take 'Slash' down wasn't helping to alleviate the genius turtle's troubled thoughts one little bit.

After what had happened in his lab, Donatello had hastily fled the lair and taken to the rooftops. As the purple-clad brother had leapt from one building to the next, trying to escape the pain, some unspeakable force had compelled him to go back to the rooftop where they had last seen Spike (aka 'Slash'). For all of his intelligence, Donnie still couldn't fathom why the heck his internal compass would guide him to the exact same place that had caused them all so much suffering.

Maybe it was some demented form of self-punishment…

A way to make himself feel even guiltier for what he had done…

"You're the reason Spike's gone! I lost my best friend because of you! It was all your fault! If you weren't such a walking disaster, he'd still be here!"

It tore Donatello apart at the seams, knowing that, all this time, his immediate older brother had been blaming him for everything that had happened with Spike. Worse yet, his older brother had acted as though he hated him for what had happened. The look of utter loathing on Raphael's face as he had said all those awful things – Well, it was something the genius turtle would never forget. Kind of like he would never forget the broken look on his red-masked brother's face after he had taken out Slash.

Donatello remembered that night far too well…

In order to stop his former pet from killing them all, Raphael had wisely opted to hit a pressure point on the underside of Slash's upper arm. The well-timed maneuver had managed to throw the psychotic mutant temporarily off-balance and the giant turtle wound up tumbling over the side of the building, down to the ground below. Although Raphael had desperately tried to save Slash from falling, the ninja in red was seconds too late.

The section of ledge that Donatello was now perched on overlooked the precise spot where Slash had crashed into the concrete below. From his current vantage point, the smartest turtle could see that the busted sidewalk, along with the torn awning that Slash had taken out on his way down, had since been repaired. Even from the substantial height that Donatello was at, he could easily see that the freshly poured sidewalk didn't quite match the color of the older concrete surrounding the area that Slash had crushed upon impact.

Somehow, that monster had walked away from what should have been a fatal fall. Which meant that, somewhere, that monster was still out there.

Oh, now there's a real heartwarming thought…

Sinking his gapped, top teeth into his lower lip to stop it from trembling, Donatello stood up and turned to glance across the empty expanse of rooftop.

Just the thought of Slash still being out there gave Donnie the creeps – almost like someone was watching him – but the intellectual turtle knew full well his reaction was only a sudden onset of paranoia brought on by his all-too-vivid recollections of this place.

Being on the very same rooftop where Slash had nearly killed him and his brothers was a little too surreal for Donatello to stomach. It opened up a floodgate of memories that he'd just as soon forget. For the past three weeks, he had tried so hard to block them out, but he could still remember every haunting detail of that night. In fact, those deep-seated memories had awoken him with a start multiple times since the incident. The recurring nightmares he was suffering from had been realistic enough to keep him wide awake for the rest of the night far more times than he cared to admit. On those particular nights when he couldn't go back to sleep, Donnie would just stare up at the ceiling, wondering if any of his brothers were also experiencing bad dreams due to their encounter with Slash, but he had yet to ask any of them about it. Not even Mikey. The smartest turtle was too embarrassed to admit that he was still having trouble sleeping because his brain couldn't disconnect from the horrifying events of that fateful night.

It was all so clear in his mind, even twenty-one days later. He could still remember Slash's callused hands grabbing him from behind and dragging him away from Mikey. He could still remember desperately trying and failing to get his younger brother's attention as he was forcefully pulled into the shadows, out of sight. He could still remember Slash roughly hauling him off to a secluded rooftop, keeping his mouth covered the whole time so he couldn't cry out for help from his brothers. He could still remember Slash almost gashing his head wide open with his razor-sharp claws, narrowly missing him and slicing through a metal roof vent instead. He could still remember Slash snapping off the naginata blade of his bo-staff, and then, viciously beating him with his own weapon. He could still remember Slash grabbing him by the left arm and slamming him around like he was just some boneless ragdoll. Lastly, he could still remember the onslaught of Slash's fists, pounding him into unconsciousness.

It was like they would never stop…

Donatello had tried to defend himself against the much bigger mutant's assault, but Slash had easily overpowered him and beaten him senseless.

Too easily…

The genius turtle subconsciously placed his right hand over his upper left arm, squeezing it as gently as possible, as if to comfort himself. He had thought his sprained arm had finally been getting better, but right now, it was throbbing something fierce. He wasn't sure if that was because he had jarred it when Leonardo had knocked him down to the floor to protect him from the explosion back in the lab, or if it was from when Raphael, in all of his anger, had shoved him. Of course, it could have just as soon been a phantom pain triggered by the sickening sense of déjà vu that he was getting from being up on this rooftop again.

Trying to ignore the sudden shiver creeping up and down his spinal column, the brainiac turtle gazed back down to the street below and found himself staring at the new stretch of sidewalk yet again.

He was once more reminded of Raph…

"All you ever do is put everyone in danger! You're supposed to be the smart one, but you ruin everything you touch!"

Donnie couldn't deny that there was an unsettling amount of truth in what his older sibling had said. He had needlessly put his brothers' lives in danger, over and over again, with his various explosions in the lab and his rather unpredictable inventions, such as the T-Pod and that laser-guided, missile-launching bo-staff. Then, there was that time he had almost killed all of them by using a Kraang power cell to fuel the Shellraiser. Oh, and Metalhead!

How could he possibly forget Metalhead?

He could still hear Raph chewing him out over that epic fail…

"Yeah, not bad, except for that part where you built the thing in the first place! And the part where it broke! And the part where it tried to kill us! And the part – "

"Okay, I get it!"

Donnie let out a lengthy breath of air that sounded more like he was deflating than breathing.

He had gone topside to run away from his problems, not make himself feel even worse than he already did.

Real brilliant idea coming back this spot, Donatello…

Plucking his T-phone from his belt to check the display, the intellectual turtle could see that he had been gone for a little over thirty minutes now. If he wanted to make it home in time for nightly patrol, he would have to head back to the lair soon. But the truth was, he didn't really feel up to patrol. Not when he knew that Raph would be there…

"You're always sorry! I've had it up to here with your excuses, Donnie! What? It wasn't enough that you almost killed Spike? Now, you almost killed all of us with another one of your crazy experiments!"

Donnie was willing to bet that his temperamental older brother had no desire to go out on patrol with him, either. He was obviously not Raph's favorite turtle right now. Not that he had ever been Raph's favorite turtle. Sometimes, Donnie felt like his hotheaded brother only put up with him because he had to. Raphael was obligated to associate with him by brotherhood, not because he actually liked him. If circumstances were different, Donnie felt reasonably certain that his red-clad sibling would have absolutely nothing to do with him. Ever.

I guess I can't blame him. I mean, I do keep trying to blow him up, along with anyone else who dares to get to know me.

Raph's supposed to be the one with the explosive personality, not me…

Again, Donatello looked down at his T-phone and let out yet another lengthy sigh. As much as he didn't want to see Raph right now, the genius turtle knew that if he didn't return home on time, it would just get Leo and Mikey all worked up over nothing. The last thing Donnie wanted to do after all that had just happened was upset the rest of his brothers. He felt as though he had done enough damage already. Having one angry brother seemed more than sufficient.

Especially when that angry brother was Hamato Raphael…

I guess it's time to face the wrath of Raph. Maybe if I let him punch me in the face really, really hard, he'll feel better and all will be forgiven…

As soon as he completed his thought, Donatello did a facepalm.

Yeah, right, genius. And then, maybe later we can braid each other's hair and sing along with Raph's favorite pop songs…

Donnie shook his head from side to side again.

If he was supposedly so darn smart, how could he be naïve enough to think for even a second that his temperamental brother would forgive him that easily?

Maybe my IQ is dropping faster than I thought…

Thanks a lot, Mikey!

A ghost of a smile played on Donatello's lips as he thought about his goofball little brother, but before long, the purple-clad turtle's features turned somber once again when it occurred to him that poor Mikey was probably wigging out over how long he had been gone for.

It was definitely time to head back to the lair. Not just because Donnie didn't want to unnecessarily worry anyone by showing up late for patrol, but also, because he didn't want to get stuck listening to a long-winded lecture from either Master Splinter or Leo on the importance of being punctual and respectful.

With a heavy heart, Donatello took one last look over the edge of the building before turning to make his way back to the lair, but he soon made the terrifying discovery that he was no longer alone on the rooftop.

Maybe he never had been…

With sudden dawning horror, the genius turtle realized much too late that it hadn't been just paranoia that he had felt earlier. His senses had been right on. Something had, in fact, been watching him and it was now blocking his path.

That something was humungous and green with spikes all over.

And unbeknownst to Donatello, that something had no intention of letting him go home.

Not ever again…

To be continued…

Author's Note: Oh my gosh! This is sooooo not going to bode well for Donnie, is it? /(O.O)\

I'll warn you in advance, the next chapter is super intense.

As always, please favorite, follow, like, reblog, review, and/or comment on this story if you are enjoying it and want me to continue posting updates. I would really appreciate the feedback and would love to hear from all of you.

Thank you very, very much for reading, my friends. ;) CJ

*Special Note: I just want to quick thank everyone who read 'Because You Weren't There.' I was totally amazed by the positive response to the story and I'm so very grateful to all of you for your tremendous kindness. Thanks, again. *hugs*