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Through The Portal ~ ROTTMNT & TMNT 2012 Crossover fic

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“Alrighty, all set to go,” Donnie mumbled to himself as he finished fitting a new tire onto the turtle tank. The genius then stood back to admire his handiwork for a couple of seconds before grabbing his satchel, throwing it over his shoulder, and making his way out to the lounge where his brothers were.


Donnie had already asked his brothers the day prior if any of them wanted to accompany him to the junkyard, however, he got no response from them as they were too caught up in a new video game they had just gotten.


Although the purple turtle enjoys his alone time - he also enjoys some company on his scrap finding expeditions. Also, more hands to carry things the merrier. 


Donnie walked into the lounge to see Mikey and Raph fully invested in the new game, his eyebrow raising as the two were almost in the exact same positions they were in when he last asked. Holding back an eye-roll, Donnie’s eyes then wandered over to see Leo chilling in a beanbag, his attention split between the game and the comic that was in his hands. 


“This is the last call if anyone wants to come to the scrap yard with me,” Donnie said, he waited a while for a reply and began wondering if anyone actually heard him. His question was then answered however when Mikey replied with a, “Sorry bro, I’ll come next we- OH RAPH AWESOME!” The two brothers then laughed and high-fived as the word Victory ran across the screen. 


Donnie blinked before shrugging and turning on his heel. Guess he’s going solo. “Ok then, I’ll be back-” 


“I’ll go with you.”


The genius turned back around to see Leo standing up.


 “...Actually?” Donnie questioned, surprised as Leo never comes on his scrap finding outings. Leo shrugged, “Sure, I have nothing better to do - plus I could get in some portaling practice,” The slider grinned, picking up his Odachi that was laying on the floor next to him. 


Donnie eyed his brother wearily. The last times Leo had come with him it either ended up in a total disaster or his brother just wanted something from him and he usually ended up getting it as well. But this time Leo sounded genuine that he wanted to come. The softshell sighed as he turned back around.


“Ok fine, go wait in the tank, I just need to grab my tech bo from my lab,” Donnie said, getting a thumbs up from Leo as he headed towards the garage. 


Surely this can’t end well.




“So while I’m collecting scraps you’re going to...?”


“Practice my portals, I already told you, Dee,” Leo rolled his eyes as Donnie scoffed. “Well excuse me for not wanting to have to leave early because you alerted the humans,” Donnie said, crossing his arms. “I really need these pieces for my next project.”


Leo gasped and put his hand on his chest, “I would never!”


Donnie raised his eyebrow and shook his head, not being bothered to bring up the last time Leo came with him. “Whatever, just remember that if you get bored practicing your portals you can always help me search,” Donnie said, turning around and pulling down his goggles over his eyes as he began his search for metal parts.


“I’ll keep that in mind!” Leo yelled after his brother as he also turned around to find a clearer spot to practice his mystic power.


After looking around for a bit Leo eventually found an open area that wasn’t completely covered in scrap parts. 


The slider pulled out his Odachi and held it out in front of him. “Alright, please cooperate with me,” Leo mumbled to the sword. However, just as he was about to slice it down to activate a portal, Leo realized that his odachi looked a little...different. Not a whole lot different, the color of the blade just seemed a little pinker than usual. 


Leo blinked, wondering if it was just his sight and when he opened his eyes again it was gone. Huh, weird. 


The slider then shook his head, pushing the thought aside as he began working on his mystic power. 


**Meanwhile in another dimension**


Donnie sighed as he rolled back his chair and looked at the current state of his desk. It was a mess. Looked as if a bomb had just hit it. 


But no, a bomb hadn’t just hit, Donnie was trying to upgrade Metalhead. Trying .


Don had so many ideas and features he wanted to give his robotic friend, but he just couldn’t do it. He had neither the parts nor the knowledge and it was frustrating and annoying the purple turtle to no end. 


The genius sighed once more. He was getting nowhere with this - maybe he should do something else, take his mind off if it… but what else can he do?


It’s been one year since they defeated the Shredder, a good eight months since they took down Kavaxus and the foot disappeared for good and of course, they’ve had their adventures after that since trouble always seems to find them; Lord Dregg decided to invade which brought Mona Lisa to earth and she stayed, they had that whole adventure with Usagi and who could forget their counterparts coming back?


But since then...nothing. Not to complain, but Donnie was bored and he can easily tell that his brothers were as well. They needed something to happen.


Donnie groaned as he got up from his chair and began heading for the door. He needed to get out of his lab, maybe get some food if Mikey hadn’t eaten it all. 


The genius opened his lab doors and stepped out into the main area to see only his little brother sitting on the sunken lounge, watching some Space Heroes. 


“Hey Mike , where is everyone?” Donnie asked, making Mikey jump a little as the orange turtle had no clue his brother was standing there. Mikey quickly realized that it was only Donnie and went back to focusing on the TV. “Dunno, think Raph’ s in the kitchen feeding Chompy and Leo’s probably in the dojo,” Mikey replied, waving his hand in the air. 


Donnie nodded slowly, “Right,” he muttered before heading to the kitchen for some food. 


The purple-clad turtle entered the kitchen to see Raph sitting at the island feeding Chompy some pizza. “That better not be the last slice,” Donnie mused, making Raph look up from feeding the alien turtle. “Keep your shell on, there’s still another two slices in there,” Raph said, rolling his eyes a little.


“Well, good.” Donnie went to the fridge, opened it up, and got out a slice. The genius then put it onto a plate and then put it into the microwave. Donnie leaned against the bench, patiently waiting for his food to warm. 


There was then silence before Raph spoke up. “What have you been doing all day?” The red turtle questioned, turning around on the stool to face his brother. Donnie groaned and rubbed his hand over his face, not wanting to think about his failure to complete his project. “I’ve been trying to upgrade Metalhead but it’s proving to be more difficult than expected.” 


Raph nodded slowly as the microwave beeped, signaling that Donnie’s food was ready. “Well, I’m going to go catch up with Mona and the Mutanimals later if you want to come, maybe Rockwell might know something,” Raph offered, shrugging as he turned back around to pet Chompy.


Donnie scoffed a little, not wanting to give Rockwell the pleasure to school him in his engineering… but he may know something to get his project up and running. The purple turtle nodded, “Alright, come and get me when you’re going.”


Raph gave his brother a thumbs up before Donnie left to go back to his lab.


As Donnie walked past the lounge with his slice of pizza, Mikey saw him out of the corner of his eye and jumped up, turning the TV off in the process. Donnie raised his brow and stopped just outside his lab as Mikey ran up to him.


“Hey Dee , can I hang out with you in your lab? I’m super bored,” Mikey asked, dragging out the super to emphasize. Donnie shrugged, “ Sure , just don’t-”


The genius stopped mid-sentence as he heard a massive crash come from inside his lab. Donnie looked at Mikey , “You weren’t already in there were you?” “What? No, I wasn’t-” Donnie didn’t let his little brother finish as he gave Mikey the plate and opened up his lab doors.


The first thing Donnie’s thought was that he had left something on, so when he opened up the doors and ran in, quickly followed by Mikey , to see the kraang portal that had been inactive for well over a year suddenly burst to life, the turtle’s eyes widened.


Mikey dropped the plate. “Holy chalupa that’s the-”


“The Kraang portal,” Donnie breathed, “But what is it- AH”


Donnie and Mikey yelped as all of Don’s work papers, scraps of metal, and experiments were picked up and swirled around the room in an instant from massive gusts of wind that came from the portal - one beaker almost hitting Mikey’s head.




The two turtle’s heads snapped towards the entrance to his lab as Leo and Raph ran in after hearing yells and sounds of Donnie’s lab being completely turned upside down.


“I DON’T KNOW THE KRAANG PORTAL IT’S-” Donnie didn’t get to finish that sentence as what felt like invisible hands grabbed him and began pulling him towards the portal and then through it. “AUGHH-”




The other three turtles eyes widened as they saw their brother disappear through the pink portal that they hadn’t seen in ages. 


Without hesitation Leo , Raph and Mikey ran at the portal and dove through it after Donnie , not knowing what world or what dimension will be waiting for them on the other side…




Leo sighed as another portal attempt failed to work. Why wasn’t it just cooperating? Was it him? All these thoughts clouded the slider’s head as anger and frustration slowly built up inside of him. Leo has been doing this for a good half an hour and has only made maybe fifteen successful portals? That wasn’t good enough. 


One more try Leo thought, then I’ll go find Donnie.


Leon closed his eyes and held his sword out in front of him. It will work this time, it has to. The slider then took a deep breath, opened his eyes, and moved his odachi in a circular motion to form… no portal. 


Leo made an angry noise as he kept moving the sword in the same motion, only to get the same result every time. 


“OH MY- WHY WON’T YOU JUST-” Leo then threw the weapon onto the ground a couple of feet in front of him, “WORK?!”  


Leo then turned his back to the weapon, not even wanting to look at it. It was useless, he was- 


Before he could even finish that thought, the slider’s brows furrowed as he heard a strange buzzing sound coming from behind him. His odachi doesn’t usually make that sound. Leo turned around out of curiosity and what he saw made him take a step back and his jaw drop.


The sword was lifting off of the ground, a bright pink aura radiating from the weapon along with pink sparks bouncing off it. Leo had no clue what was going on. 


“What the- DONNIE!” Leo yelled for his brother as the energy surrounding the odachi and the wind seemed to intensify. The wind was so strong the slider had to lean into it just to stay standing.


Leo wasn’t standing for long however as what looked like a portal generated out of the sword, sending another gush of wind outwards which sent the blue turtle flying backward before landing roughly on his shell. 


Leo sat up immediately to see the portal formed in the air. It definitely wasn’t one of his portals, no, it was bright pink and triangular instead of his blue, circular portal. Leon has never seen anything like it in his life. 


Then, just as the blue-clad turtle didn’t think anything could get any weirder, four big figures dropped through the mysterious portal and landed with a thud on top of each other. Leo blinked as the portal closed quickly after and the odachi dropped to the ground as if nothing had happened. 


“LEO WHAT’S WRO-” Donnie started, running towards his brother after picking up strange mystic energy coming from the area his brother went off in. The softshell stopped dead in his tracks and cut his sentence short however when he saw four mutant turtles lying on top of each other. 


Leo stood up next to Donnie, his eyes wide and locked on the newcomers. “They’re-”


Donnie dropped the bunches of scrap metal that he was holding in his arms.