A/N: This is AU from the 'Good Genes' arch. Everything is similar expect the fact that Don is less aggressive and more intelligent (a little). I got the idea from a piece of artwork on DA. It was of the Hulk hugging Spider-man gently while he was injured and the idea just sparked in my mind. Anyways, hope you like it. Review if you think I should continue if not I'll just scrap this.

He sneaked his way towards the wild assortment of pipes, crouching low and clinging with skill on the cool metal. He glared down wondering if he would be found from his simple hiding location. However, he didn't shooting himself down so easily. The darkness was his ally and he moved silently above the the rusted pipes like floorboards on ground. He shifted his weight so that he could lean on his right side, sweeping his left foot out and his hands in front of him to keep balance. Suddenly, he heard a noise after a long wait. The footsteps were loud and clumsy. Not caring where it stepped as it made its way down the narrow tunnel. He carefully craned his neck over the disarray of piles and watched the creature appear from the distance into his line of sight. It was crouched low, long snout moving just inches above the ground and sniffing.

The other swallowed hard, keeping silent and wondering if he should move away to avoid being caught. The creature's hearing was so acute it was ridiculous and to be honest he was sure that he was cheating now. The creature made a small deep moan of interest as he picked up on the familiar scent.

Suddenly, the creature stood on two legs and the other gasped. He had forgotten how tall the creature actually was. He tested his position as he moved ever so lightly towards the next pipe behind him. He clung to the pipe underneath him and turned to face the endless assortment of red looking pipes. Maybe he could reac-

"Ahhh!"

The creature grabbed hold of him unexpectedly and dropped him roughly to the ground into the sewage water where it stood. It took a moment to process everything considering it was so sudden and quick. He hadn't expected to be found by his brother so quickly.

"Come on," Michelangelo rubbed his bottom as he stood from the disgusting water and onto solid ground, "You totally cheated, Donnie!"

The creature merely stared at the small turtle with neutral eyes. Donatello lowered himself onto all fours but his hind legs were bent still and his bottom moved back and forth. Mikey chuckled, realizing that his large brother wanted to play again.

"I'm kinda hungry right now, how about we play later and get something to eat first?" Mikey asked the much larger mutated terrapin. Donatello stopped to look up at his brother and tilt his head as if confused of what his brother had said. "Eat! Yum yums!" Mikey explained further to his once genius brother. Donatello was limited on communication but he did understand somethings. Donatello seemed to throw this idea back and forth in his mind before letting out a large puff of air through his nostrils. Mikey smiled at his brother with a worried stare.

"C'mon, big bro! I'll make you an awesome sandwich and I'll put in extra ham just the way you like it." Donatello stood on his two feet once more and moved his short tail back and forth slowly. Mikey took the silence as a yes and also taking into account that his brother wasn't growling and roaring at him angrily..yeah it was a good thing. Mikey watched his brother for a while before hastily running in front of him to do a front flip then beckoned for the other to follow. Donatello followed quietly despite his heavy breathes and loud stomping.

As soon as the two arrived back at the lair, Mikey was bombarded with questions by the oldest.

"Where did you go! How could you be so..so stupid! You can't just drag him out like that!" Leo fumed angrily at the youngest.

"We were just playing a game!" Mikey countered, "Donnie likes playing hide and seek."

Leonardo pressed two fingers between his eyes and sighed deeply trying to calm himself. The youngest just didn't understand but he couldn't really blame him. Leo looked behind Mikey though he really didn't have to. Donatello was laying on the ground with his arms tucked in and his head resting on top of them. His menacing red eyes were narrowed showing signs of drowsiness from their play time. Leo felt a little relieved that he didn't have to watch over the larger sibling and turned his attention back to Mikey.

"Mikey, I know you're trying to help Don but right now he needs to stay here."

"The poor guy just needs to stretch his legs!" Mikey argued, "He's not some animal, Leo, he's our brother!"

"I get it," Leo spat back impatiently, he turned back to Donatello who was now sleeping peacefully near his once work station. "However, you need to understand that Don is..well he's really unpredictable right now."

"We've been through his, Leo," Mikey groaned and moved past his brother towards the kitchen, "He isn't going to hurt us! He knows us, I know and he knows, ya know?"

Leo felt his eye lid twitch. He fell silent finding no use arguing with his brother any longer and sighed. He really wanted to believe his carefree sibling but he just couldn't. Every time he looked at his mutated brother he couldn't find the familiar care that he once had with Donatello. His brother was gone and replaced with this..monster. He hated to think it but there was no other way of putting it lightly for him. Leo was sure that the creature- his brother could feel it too. It might explain why his once sibling was so distant from him compared to the others.

Leo remembered when his once brother almost hurt Master Splinter by a furious swipe of his enormous claw. Without really thinking Leo stabbed Donnie's large arm in retaliation much to everyone's horror. He hated how easily he had made that decision but he didn't regret it. Don could have killed their father with one hit from his claws. Don didn't know his own strength in this form but everyone was putting in their time and patient to help him. Leo could still see the scar that he had left on his brother.

"Awww did he fall asleep? How cute!" Mikey cooed dumbly as he emerged from the kitchen with a large sandwich in hand. Leo watched on alert as his brother knelt besides the sleeping beast and stroked the top of his head. Leo's heart stopped when Don opened his eyes at the touch but remained still. He seemed to be enjoying Mikey's loving affection towards him. Leo could have sworn he heard the creature purr. Donatello's eyes narrowed once more before shutting and exhaling deeply in relaxation.

Mikey took a bite out of the sandwich, chewing hungrily with gusto. Leo returned to the living room at least close enough to his brothers just to safe as always. Mikey ignored him as always. Biting into his sandwich again as he scooted closer to his mutated brother and turned on his bottom to lean back and rest his shell against Donatello's massive form.