Chapter 2

Mike looked behind him toward the door of the dojo for what had to be the hundredth time in the past hour. Leo, Raph and Spike had been in there for hours, and Mikey had tried to listen at the door a couple times, only to be scolded by Donnie who was stuck out here with him. 

“Come on dude, you can’t say you’re not curious too,” Mikey accused as he turned to face his slightly older brother. 

“I am curious, but I know how to practice a little something that I call ‘patience’.” Donnie said smiling when Mike groaned and fell sideways on the couch so that he was laying down. 

“Patience is BORING bro, shell I’d be happy if someone just opened the door long enough to tell us if Spike was staying or not,” Mikey said. 

“I don’t think Master Splinter would just kick him out, he let Leatherhead stay here after all,” Donnie pointed out, Mikey smiled and nodded. 

“I think it would be awesome if he did stay, it would mean I’m not the youngest any more!” Mikey said with a wide grin as he sat back up to look at Donnie. 

Donnie raised an eyeridge at his younger brother. “How do you figure he’s younger than you?” 

“Because I’ve been here longer,” Mike said still grinning. 

“It doesn’t work that way Mikey, Spike could very well be older than you are,” Donnie pointed out but Mikey shook his head. 

“No way dude, his mutation day was yesterday, mine was fifteen years ago, so I’m totally older,” Mikey said confidently and Donnie decided to let it go, he already knew that he wasn’t going to win this argument. So the olive green turtle turned his attention back to his laptop, and Mikey went back to watching the dojo door. 

The silence only lasted for less than three minutes before Mikey looked at DOnnie again. “How much longer do you think they’re going to be in there?” Mikey asked.

“They probably have a lot to talk about, trying to decide where Spike is going to sleep, and Leo still has to convince Splinter to lift my punishment, and allow me back into my lab so I can make sure that Spike’s mutation is stable,” Donnie said and Mikey stared at him tilting his head in confusion. “I have to see if Spike is healthy,” Donnie said simplifying it as much as he could. 

“He looked fine to me D,” Mikey said shifting around on the couch so that he was sitting upside down, his head down by the floor and his feet hanging over the back of the couch, his attention focused mainly on the TV now that one of his favorite shows had come on. 

It was nearly another half an hour before the dojo door opened, and Mikey who had seemingly had his full focus on the TV jumped to his feet to watch Leo and Raph come out of the dojo followed by Spike. The first thing that Mikey noticed was that Leo didn’t look to happy, however Raph looked extremely pleased, it was a weird switch as usually Raph was the one to look unhappy after a long talk with Splinter. 

“So…” Mikey trailed off looking at his two eldest brothers. “Is he gonna stay?” Mikey asked looking over at Spike. 

“Yeah, he’s staying,” Raph answered still looking very happy about this. 

“For now,” Leo added, earning himself a glare from Raph. 

“Why are ya so against him staying Leo?” Raph snapped. “He ain’t done anythin’ to you!” 

Leo clenched his hands into fists turning away to ignore his brother, turning his attention instead toward Donnie. “Splinter said you could use your lab, run whatever tests you need to on Slash,” Leo said. 

“...uh...Slash?” Donnie asked. 

“I wasn’t to fond of the name Spike,” the larger turtle explained. Mikey grinned widely as he stared at the larger turtle. “What?” Slash finally snapped glaring at Mikey. 

“Just trying to decide if you look like a ‘Slash’ or not,” Mikey said. “I’m the one who names things around here, it’s kinda my thing.”

“Just ignore him, Slash,” Raph said and looked to Donnie. “Were you gonna run those tests now, or later?” He asked. 

“Now would be better I think,” Donnie said and went to his lab, Mike followed after his slightly older brother, before poking his head back out the door to see the others still standing there. 

“You comin’ dudes? D can’t run tests without his test subject,” the orange banded turtle grinned ducking back into the lab when Raph shrugged and started leading Slash toward the lab. 

----------------x

 They had been in his lab for nearly the whole day while Donnie ran test after test, trying to figure out if the mutagen had had any negative side effects on Slash, though from time to time, Donnie seemed to forget that he had an audience as he ran his tests. “Fascinating,” Donnie said as he wheeled his chair from his computer desk over to where he had the microscope set up, “Absolutely fascinating,” he said again. 

“You're doing it again D,” Mikey said and Donnie glanced up at his younger brother who had seated himself on the corner of his desk. Glancing away from Mikey the purple banded turtle looked over to where Spike was seated on the cot, Raph standing not to far away from his former pet turtle.

“Sorry,” Donnie apologised wheeling back over to his computer and typing in a few things before turning to face the other two turtles again. “I think I've figured out the base origin of Spike's mutation,” Donnie said.

“I've told you already, my name is Slash now,” Spike said with a growl.

“Right...sorry,” Donnie rubbed the back of his head nervously before clearing his throat and continuing. “My hypothesis was correct that it was in fact the explosion that caused this mutation, but there's a bit more to it than that,” Donnie said standing up from his chair watched closely by both Slash and Raph, while Mikey took over the abandoned chair, sitting it and wheeling it from one end of the room to the other.

Donnie ignored Mikey focusing on grabbing a chart and pinning it up on the wall. “This is a diagram that I created, it maps out our basic anatomy,”

“I didn't come in here to sit through Dr. Don's science class,” Raph said crossing his arms and glaring at Donnie.

“And if I don't explain all of this, you're not going to understand anything I tell you about what I found out from Slash's mutation,” Donnie said.

“I'm not going to understand anything you say anyway D,” Mikey said as he wheeled by again on the chair.

“Do you guys want to know any of this or not?” Donnie asked sounding annoyed.

“I'd like to know,” Leo said from the doorway, Donnie looked over at his eldest brother giving him a small grateful smile. Leo made his way over to get a better look at the diagram that Donnie had pinned up, even if he didn't fully understand it, Donnie was still happy that one of his brothers at least tried.

“I'll try and keep it simple,” Donnie said reaching out and stopping the chair as it rolled by again, the sudden stop sending Mikey falling to the floor.

“Not cool bro,” Mikey pouted but made no move to stand up.

“As I was saying,” Donnie said looking over at Raph and Slash. “Us four,” Donnie indicated himself and his three brothers. “Are basically new species, a turtle human hybrid,” he began explaining but paused when he saw the confused look that Mikey was giving him. “We are half turtle, half human,” he simplified, “Slash on the other hand has retained most of his turtle genetics,”

“So Slash is basically just a very large turtle that can talk?” Leo asked raising an eye-ridge at his genius brother.

“Yes and no, this is where it gets very complicated, the reason we took on more human traits is because we were exposed to the pure mutagen, right after being handled by a human, Slash on the other hand wasn't exposed to the same mutagen as us, it was modified drastically from it's original form, and was mixed with April's DNA,” Donnie said looking at his two older brothers hoping that they at least understood.

“So he's just a very larger turtle that can talk,” Mikey said repeating Leo's earlier statement.

“Yes Mikey, he's a very larger turtle that can talk,” Donnie said with a long sigh, looking up when he felt a hand on his shoulder, Leo smiled at him.

“Sorry Don, I know there's a more complicated explanation behind this whole thing,” Leo said and Donnie returned the smile.

“It's alright Leo, I'm used to this by now,” he said then turned once again to look at Slash. “I would still like to run a few more tests, if you're okay with that?” Donnie asked.

“Why do ya need more tests Don?” Raph asked. “He's been here for three days now, his mutation hasn't messed up his head at all,” Raph insisted looking to Slash. “Ain't that right buddy?” He asked and Slash nodded his head in agreement.

“I don't feel much different from before, just a lot bigger and stronger, and things make a lot more sense to me now,” Slash confirmed.

“Still, this mutation is very different than what we are used to,” Donnie insisted. “And it's not only Slash’s mental health that I am concerned with, there's a lot of physical changes as well, I've confirmed that you are still more 'turtle' than we are, but how much more? Is your anatomy the same as ours, or have you taken on more human traits there as well because of April's DNA.”

Mikey let out a groan falling backwards onto the floor, tilting his head back to look at Slash. “I think Donnie's trying to bore us all to death,” he said his frown quickly being replaced with a wide grin. “Dude! I just realised that you haven't even tried pizza yet!” Mikey said jumping to his feet and running out of the lab, his mind set or rectifying the fact that Slash had yet to try pizza.

“Com'on Slash, let's get outta here before Mikey tries to poison us,” Raph said.

“Don't go too far Raph,” Leo called out seeing both Raph and Slash heading for the door. “We've got an hour before we leave on patrol,” Leo said frowning when Raph only waved his hand in acknowledgment that he had heard him, and continued on his way out of the lair. 

TBC 

Okay so I know that this is a super short chapter, I am sorry for that, I kind of didn’t know where to go after this, and as the next part I am writing actually takes place a few months from this point, I didn’t want to put such a huge time jump in the middle of the chapter. So...short chapter, but at least things are getting written! 
That being said, I am currently looking for someone who would be willing to beta read my TMNT fics for me, I have this one, and I have planned a couple more as well. And while I have a totally awesome beta reader for my Harry Potter stuff, she doesn’t know much about TMNT.