A/N: Yooo, so, long time no see. This is just a little something that crossed my mind in the downtime of writing my big Ninja Turtles project (coming soon! 4 chapters down!) I figured this would explain a lot, and it sounds like something Donny would do. If you enjoyed it, let me know! Read and review, please!

The brothers collapsed in groans after a particularly hard morning practice. As Splinter dismissed them, they wearily trooped out of the dojo, shedding their weapons as they walked. Don stuck his by his lab door as he stretched, trying to roll the kinks out of his muscles. Leo managed to sheath his katanas back on his shell, and Mikey clattered his nun-chucks on the table as he moved to get a snack. Raph didn't even have the energy to throw his sais into the punching bag… he just dropped them were he walked.

"Man, I am beat," Mikey groaned from the kitchen. "I think even my aches are aching!"

"That 'training session' felt like an actual battle," Raph agreed, belly-flopping onto the couch.

"I'll still be feeling this tomorrow," Don yawned, cracking his back.

"Seconded," Leo panted.

There was an uncharacteristic silence of about twenty minutes while the turtles recuperated, which was promptly broken by a bouncing Michelangelo.

"Who's up for some movie remakes, guys?!" he bounded happily through the lair, jumping and kicking and twirling his nun-chucks. The others groaned as the hyperactive turtle proceeded to spar against invisible vampires.

"How are you already so active?" Leo asked, partly in wonder, and partly in dismay.

"Donny, I told you not to plug him in," Raph said. Don shrugged.

"Yahoo!" Mikey suddenly paused, then put his hands on his hips and tapped his foot. "Guys, come on! We were totally going to reenact that fight scene from Winter Soldier- only make it better!" He scooped up one of Raph's sai's and tossed it at him. "Hello?"

Raphael simply caught it, then rolled over on the couch, hugging it to his chest. "Go away, Mikey," he groaned into the muffled cushion.

"Sorry, bro, but I think I got my second wind." He tapped the tired ninja with the other sai. "I'm way too wired! Leo?" He cast his classic puppy-dog look at the leader, who resolutely avoided looking in his direction.

"Donny!" he cheered, running by the collapsed genius. "Let's do this!"

"Mikey…"

Too late, Mikey had already bounded over to Don's discarded bo staff. "We'll just pretend that I'm Captain America and you're- HOLY SHELL!"

Everyone turned as Mikey was pulled down on his face with a thud. He stood up quickly, eyeing the staff as if it had suddenly turned evil. "Donny, what did you do to that thing?"

"What?" Leo asked, rising from his spot. They slowly made their way over to the youngest. "What happened?"

Mikey pointed. "That thing's heavy!"

"Nah, Mikey, you're just still weakened from this morning's practice," Raph snickered. He bent down to pick it up, and Leo noticed a brief smirk appear on Donatello's face.

"What the shell?" he exclaimed, staggering for a moment. He recovered and looked bewilderedly at the wooden staff, trying to divine how in the world he had misjudged its weight that badly. "Donny, I remember practicing with some of these when we were first startin' out, and no way were they this heavy!" He passed it to Leo, who noted with surprise the weapon's density.

"Well, you're right, those are pretty light, but I kind of… doctored this one," Don explained apologetically.

"With what? Lead?" Leo asked. He handed it to Don, who twirled it with ease.

"Not exactly. Have you guys ever heard of petrified wood?"

Raph and Mikey shook their heads, but Leo remembered a documentary about it once. "That had something to do with minerals getting into the wood… Don, did you turn your staff to stone?"

"Sure feels like it," Mikey muttered.

"I petrified the wood. Well, not completely. I still left enough of the organic material inside so that it would have a little flexibility when I need to maneuver it. And I selectively chose which chemicals and minerals to expose it to, so that it would certainly be more durable, but not basically a rock pillar." He swung the staff around in a few basic katas before placing it on his back. The others cringed as he did so.

"Bro, you're making my back hurt just looking at you," Mikey moaned, turning away. "Oww… I gotta lie down."

"At least it got him outta his hyper phase," Raph approved, heading back towards the couch.

"Well, I guess that explains why it doesn't break when you smash missiles and blades with it," Leo mused, gazing at the bo and turtle thoughtfully.

Don shrugged. "There was a way to give it more oompf so I followed it." He yawned again and rubbed his eyes, catching Leo still looking at him when he opened them again. "What is it?"

"Remind me to never joke about your 'stick' again."