Disclaimer: TMNT are the property of Mirage Studios, Funimation and probably a whole bunch of other people who aren't me. No copyright infringement is intended.

Author's Note: Don't ask me why, but I was watching this episode the other day and the scene where Donnie drops one of Raph's sais just got stuck in my head. Donnie being the weakest fighter is a pretty common theme in TMNT fandom, so I don't think I break any new ground here, but I've always had the feeling that even though his brothers knew he was the least proficient, they never really begrudged him needing the extra protection. This scene kind of grew out of that. Also, I really like throwing Raph and Donnie in a room together to see what happens.

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Genius at Work

An episode tag to What a Croc

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"Your problem is, you're a super-genius."

Donatello leaned back on his hands and laughed a little. "That's not usually what my problem is," he said a little ruefully. He waved away the hand Raphael offered him and got back to his feet himself. He was starting to tire a little, but most of it, Raph judged, was frustration with himself. Donnie usually learned things so fast that it was easy to forget he needed teaching and practice, just like everyone else. Fighting was the one area where he didn't excel like a college student in a kindergarten class, though. That tended to backfire on all of them when Donnie got mad at himself for not picking it up as fast as he did other things, and when whoever was teaching him forgot that Donnie had his weaker areas, just like the rest of them.

Raph usually didn't forget that, at least not as much as Donnie himself did. "Being a super-genius is always your problem," Raph said. "You can learn Utromese in less than an hour so you start expecting you can do everything as fast. And weapons practice ain't like that, Donnie." He grinned and tapped Donnie's temple with the point of a sai. "This muscle's had a lot more practice than the rest of them. You gotta be patient and let them catch up."

His brother made a face at him. "It shouldn't be this hard," he said. "If Mike or Leo were in here with you, you'd be done by now."

That was true, but it didn't mean he was going to let Donnie know that. "I wouldn't be in here with Leo," Raph said, "and we both know it. And Mikey's as good with physical stuff as you are with mental stuff, so that's not a fair comparison. You wouldn't get mad at me if I didn't pick up nuclear physics in less than one day, would you?"

"Raph," Don said with a mock seriousness that already had the side of Raph's mouth curving into a smile, "with your temper? I am never going to teach you nuclear anything."

"Smart ass," Raphael said, letting his amusement show and was rewarded with a wide grin. "You know I'm right."

"You usually are," Don said. "I just get tired of holding you guys back."

Raph stopped himself before he could raise an eyeridge or blink in confusion. "You don't hold us back from nothing."

"That's why you spend half of every fight we're in saving my neck?" Donnie countered. He still had the two practice sais in his hands and he spun one absently, the movement fluid and perfect. "Why Leo lectures me on all the times I've endangered the rest of you by needing protection? You think I don't see the look on your faces when you take out enemies who were gunning for me that I didn't even see?"

"You could turn into SuperNinja overnight and I'd still watch your back in a fight," Raphael said. "I watch Mike's and Leo's too. And Casey's but that's because he's an idiot."

He frowned a little as an unpleasant thought occurred to him. "You think I watch out for you because I think you're incompetent or something?"

Donatello shrugged. "Why are we here, Raph?" He hefted one of the sais pointedly. "Because I can't even use a sai properly in a fight. I dropped one while we were fighting Stockman's turtle-bot. What if Mikey hadn't taken it out right when he did?"

"Then I woulda cut its other arm off," Raphael said. "Or Leo woulda kicked its head off, or Mikey and Leatherhead would have done something. Or maybe you woulda picked up the other sai and thrown that one, too, for pete's sake. What," he challenged, hoping to get a rise out of Don, "you were planning on just standing around while it finished us off?"

"You know I wasn't." Don didn't rise to the bait, which was a bad sign. Brain boy got way too introspective sometimes and that was when he tended to fall into a funk. It was easier if you could draw him into an argument. Half the time you could make Donnie argue himself out of it. Raph was usually pretty good at it.

Raph twirled the sai in his left hand and attacked with the one in his right. He swung at Donnie's face and nodded with satisfaction when Don reacted automatically, catching Raph's attack with the practice sai. "You're learning."

Donatello shrugged. "And if you were pressing this attack, I'd have the prong of your sai sticking out the side of my throat."

"And if you were reacting the way you would in a real fight, you'd have ducked, or knocked my feet out from under me." Raph twisted his wrist, pushing down with his right hand and was rewarded when Don pulled his sai free and spun to the side, putting himself just out of Raph's arm's reach. "You know why Leo lectures you after a fight gets too close?"

"Because Leo would die if he didn't lecture someone at least once a day?"

Raph chuckled. "No. Okay, maybe. He lectures you cause Leo scares easy. We both know that." He waited until Don nodded almost reluctantly. They did both know that, even if it was kind of weird to think about it. But Leo did scare easy where they were concerned and he never scared more easily than when he thought he might lose them. "And when Leo gets scared, he gets angry."

"Like some other brother I could name," Donatello pointed out and Raph shook a sai at him.

"I don't know what you're talking about," Raph said. "You scare Leo, so he lectures you. It makes him feel better. He gets some of the anger out, and he tries to make you realize how you could keep it from happening again. It's not cause he thinks you're a screw-up, Don." He grinned. "He lectures me all the damn time, too, remember. And I don't think I'm gonna hurt your feelings by saying I'm a better fighter than you are."

"You're a better fighter than all of us," Donnie said. "Sometimes you're the only one I don't worry about."

Raph blinked at him. "Thanks. I think."

"You beat everything the word throws at you," Donnie said. "It's admirable. Half the time I think you're immortal."

"I ain't immortal," Raph said. "I'm not even that good, though I'll kick your sorry ass if I ever hear you tell Leo I said that. I'm just too stubborn to die. It's one thing you and me have in common."

It was Donnie's turn to look surprised. "You think we're alike?"

"You don't?" Raph countered. He didn't let himself get defensive. "Not in the brains department, we ain't, I know that, but-"

"Oh, shut up," Donatello said, planting his hands on his hips. "I thought we settled that years ago."

They had. "Think about it, brainiac," Raphael said. "It'll come to you. And yeah, I think we're alike, a little. I mean, you ever meet anyone else half as stubborn as you are?"

"Look who's talking," Donatello said.

"So I know what I'm talking about." Raphael settled into a defensive stance, nodding approval when Donatello copied him. "We like a lot of the same kind of music. You and me both have more interest in the human world than Leo or Mike. We both want to travel someday. We both get mad at being cooped up down here, sometimes. And we're both guard dogs."

"Guard dogs?" Don echoed him doubtfully.

Raphael spun out of his defensive stance with a kick that Donnie avoided easily, and a downward jab of his sai that Donnie parried automatically. Raph used momentum and greater strength to his advantage and pushed Donnie's hand down and to the side, leaving him open for a second attack. Donnie didn't push back, instead he let the force of Raph's attack drive him to the floor, ducking the second blow while he turned the captured sai around, using Raph's strength against him.

"Not bad," Raph said, releasing the hold he had on Don's sai before his wrist could twist far enough to break. "But you shouldn't forget you've got two weapons. Use the other one. Stab me in the knee or something."

That was something he hadn't considered before they started training, but it made sense. Donnie fought with one weapon almost exclusively and had for years. Having two weapons in his hands was something he had to get used to. "I know you can multi-task," Raphael said. "I've seen you type with one hand, while writing equations with another hand and still entertain Mikey. So this should be easy for you."

Donatello got thoughtful at that, and Raph knew he was taking the lesson to heart. "Guard dogs," Raphael said. "Both of us. But I do it with my fists. Someone threatens my family, I get in there throwing punches and breaking bones. You do that if you have to, but it's not your first impulse. You guard us by making sure no one gets close enough to threaten us in the first place. You build motion sensors and surveillance systems and alarm panels. You put in sleeping gas and god only knows what else out there. You build hidden entrances to the lair with coded access, and escape routes for a fast escape. You make this place as safe as you can without packing us all up and moving us to the moon. I'm worried one day I'll piss you off and you'll take my voice recognition out of the alarm system."

"I'm thinking of putting in retinal scanners," Donatello said. "Just for kicks. Mikey would think it was cool."

"Those things make me nervous," Raph said. "Laser beams near my eyes makes me jumpy."

Donatello grinned at him. "Maybe I'll just put one on your room, then."

Raphael pointed a sai at him. "Don't think I won't break both your legs if I gotta to make a point."

Don started backing away slowly. "Maybe the bathroom."

"Man, you asked for this." Raph slipped his sais through his belt and tackled Donnie around the waist.

The weapons practice rapidly degenerated into a wrestling match and Raph caught a glimpse of Leo sticking his head in the door to see what all the commotion was, then making himself scarce before one or both of them could drag him into it.

"Say Uncle," he demanded triumphantly. He had Donnie on his back, his hands pinned to the floor – not a comfortable position, since his shell made the angle awkward and Don's shoulders had to be burning.

Donnie struggled for a second, but he didn't have any kind of leverage in that position. "All right, all right. God, you weigh a ton."

Raph chuckled and deliberately put more of his weight on Donnie's chest. "You're not helping yourself any, you know that."

Donatello made a strangled sound and feigned passing out.

"Smart ass," Raph said fondly. He leaned forward until his mouth was right beside Donnie's ear. "I watch your back because you're my brother and I love you," Raphael said. "Not because I think you're weak, or because I don't trust you in a fight. I'd go to hell with you watching my back and never worry about my own safety. The only thing that scares me going into a fight is that I won't be good enough to save you or Leo or Mike or even that goofball Casey. I never worry that you aren't good enough."

He felt Donnie's heartbeat kickstart into high gear and decided it was enough touchy-feely shit for one day. "So stop your angsty bitching. That's Leo's gig." He knocked Don's head against the floor once, just hard enough to make his point. "You hear me?"

"Yes, sir, Mr. Raphael, sir."

Raph snorted as he used Donnie's plastron to push himself up off the floor. He offered Donnie a hand up and this time his brother accepted it. "And Leo says I'm the smart ass."

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