"You wouldn't believe it!" Raphael said.

"We were out minding our own business…" Donatello said.

"When some evil ninja appeared out of nowhere!" Katsuragi said.

"These girls were really scary." Hibari said.

"And tough." Leonardo said. "We gave everything we had, but they wouldn't go down."

"I even knew one of them." Asuka said. "I thought we were friends, but she was an enemy this whole time."

"Michelangelo got beat up by a little girl in a black dress." Yagyu said.

"Did you have to mention that part?" Mikey asked.

"All right. That's enough." Kiriya said calming everyone down onto the lounge couch. "It's clear now that the evil shinobi that are targeting us are students from Hebijo Academy."

"I've only heard stories about them." Splinter said. "I didn't think they'd be so bold. After all, we have their elite students as you call them outnumbered."

"That didn't really do much." Donatello said. "Even with us working together, they brushed it off like it was nothing."

"I have heard rumors of Hebijo going through a more strict training regimen lately," Kiriya said, "But I never could get any more information about them."

"But what do they want?" Ikaruka asked. "They could have killed us then and there, but they didn't."

"There must be something else that they wanted." Splinter said. "Attacking you must be their way of saying they're willing to go through you to get it."

"And I can only think of one thing at Hanzo they'd want." Kiriya said. "The Super Secret Ninja Art Scroll." The girls widened their eyes while the turtles looked confused.

"The what? That seems like a bit of a mouthful." Donnie asked.

"The Super Secret Ninja Art Scroll." Splinter said. "A source of great shinobi power. It's hidden here within the school walls."

"We actually have something like that?" Raphael asked. "Then why aren't we using it against Hebijo?"

"Because it's forbidden." Kiriya said. "The scroll is a sacred and dangerously powerful artifact that Hanzo Academy protects. We're not allowed to use it."

"So now, all we can do is protect it." Splinter said. "We're going to have to train harder in the event his Hebijo girls strike again."

"We understand." Leo said. "We'll train even harder."

"Why don't we just learn how to transform?" Donnie asked. "Ikaruga and the others can clearly do it. Why can't we?"

'Yeah!" Mikey cried out excitedly. "I can just picture myself throwing a scroll into the air and changing into a robot warrior anime style!"

Splinter frowned. "I'm afraid… you won't be able to."

"What do you mean?" Leo asked.

"The truth is… none of us are able to transform, not even me anymore." Splinter confessed.

"This is news to me." Kiriya said.

"It appears that whatever this ooze did to us also affected our natural ninja skills in a way I couldn't have foreseen." Splinter said. "We're still able to move and think like shinobi, but no matter how hard I try, I can't seem to transform anymore."

"Then… does that mean we can't either?" Donnie asked.

"Not unreasonable to think so." Splinter answered.

"Aww." Mikey groaned. "My robot."

"Then we'll have to find some other way to train you guys." Asuka said. "Next time, we'll be ready."

"Glad to hear that." Kiriya said. "Now, you're all dismissed."

The turtles and girls got up to leave. But right before they left, Hibari grabbed Donnie's hand and sneaked him away from the others.

"Hibari, what are…"

"Shh." Hibari said. "Sorry, Donnie, but I need you to look at something. It's important."

Donnie sighed. "Fine. What is it?"

Hibari brought Donnie to her room where she opened up her backpack. She reached in and pulled out something that spooked the purple-bandana turtle. It was the same metal creature that Hibari found earlier.

"What the shell…" Donnie yelled.

"Shh!" Hibari said.

"Hibari, what is this thing?" Donnie asked.

"I don't know. I found it on the beach underneath the debris from our fight." Hibari replied. "I think we may have hurt him."

"You do realize that's a mysterious robot, right? Not some lost puppy." Donnie said. "I mean, who built this and why?"

"That's kinda what I want you to figure out." Hibari said. "I want to show it around the school, but I worry it might be booby trapped. Do you think you can look at it to see what it is? You are the smart one."

Donnie said taking the robot. "I'll see what I can do. But this technology… I don't know what to make of it. This might take me all night to figure out."


"And that one night is all that we need." Said the black man in a white lab coat. He was surrounded by a high-tech laboratory and he gazed at a computer screen which displayed Donatello's face.

The door opened up and the Shredder walked in wearing his armor. He was accompanied by Master Suzune and the puppeteer, Haruka.

"Dr. Baxter Stockman." The Shredder addressed. "Any progress."

"Not yet, but I'm more than likely to get you that scroll tonight." Answered the man named Baxter Stockman. "That naïve girl brought my Mouser over to Hanzo Academy. If you're school is anywhere there, we'll find it."

"It seems your diversion worked after all, Haruka." Shredder said.

"Thank you, Master Shredder." Haruka said. "But I must admit, I really hoped I would take that Hibari in as my puppet. Oh, well. I will next time."

"The only snag is that she gave it to one of the turtles who appears to be tech-savvy." Baxter said.

"Is that going to affect the outcome?" Shredder growled.

"Of course not. It just means I'm going to have to put up certain security measures wirelessly to hide the Mouser's true purpose, and I'm going to have to be vigilant to do so until he takes a break."

"Right, the one with the purple bandana." Suzune said. "Yomi told me this was a smart one, like a super genius."

"A super genius turtle, huh?" Haruka asked with a delighted smile. "I wonder if it's possible to make a doll out of a turtle mutant."

"Better yet, I'd like to know how a turtle can even mutate into this." Baxter said. "The very idea of genetic mutation on this scale should only be science fiction at this point."

"Once we complete out objective, I'm sure we can give you one of the turtles to dissect." Shredder said. He turned around and prepared to leave "For now, keep me updated for any changes. Suzune, keep an eye on Stockman to make sure the plan falls through."

"Understood, Master Shredder."


Sure enough, Stockman's plan worked. Late that night, Donnie yawned while trying to hack the Mouser. Eventually, he dozed off and dropped his head on his desk before beginning to yawn. That's when the Mouser went to work. It disconnected itself from Donnie's computer and hopped off the desk.

The Mouser left the lab and looked to its left and right before scurrying into the main lobby. A red light shined from its eye and it covered every inch of the room. When it was done, it moved onto the next. Careful surveying. Scanning. Moving on. Rinse and repeat.

Eventually, the Mouser found its way to the principal's office. It scanned the area, and unlike the other rooms, there was a reaction. On the wall, a square spot was emitting a strange reaction that made the Mouser stopped. It dugs its foot claws to the wall and climbed up. Once it reached upwards, it broke through the wall with its robot teeth. What was revealed was a brown door with a knob on it. The Mouser reached its teeth for the knob, but suddenly, a recorded voice echoed from the door.

"Spy."


"What was that?" Stockman asked.

"It's a pass phrase." Suzune said. "It says something and we have to give it the appropriate response."

"What?" Stockman asked. "My mouser can't say anything! Why didn't you tell me we needed a password?"

"I didn't know." Suzune said.

"This is bad." Stockman said. "Look, my mouser has a laser function. Maybe I can blast…"

"That's a bad idea." Suzune said. "That'll alert Master Kiriya and your robot won't get away with the scroll."

"Then what am I supposed to…"


"Well, isn't this something?" asked a voice from the door. The mouser turned seeing Yagyu standing behind it. She pointed her umbrella at it. "I don't know what you are, but I won't tolerate any spies."

She fired a wind blast from her umbrella which the Mouser dodged. It scurried around the room quickly avoiding her attacks.


"Well, our cover's blown." Stockman said. "As soon as we deal with her, we're blasting that vault open!"

The Mouser peeked out of its hiding place behind the desk and fired a laser beam at Yagyu. The girl easily dodged and went behind it where she kicked it right to the wall. The Mouser barely stood up right when Hibari appeared at the doorway.

"Yagyu, what's going on?" Hibari asked. She gasped as she saw the Mouser. "What's that robot…"

"Hibari, get out of here now!" Yagyu yelled. "I don't want you to get hurt!"


Suddenly, an idea flashed in Stockman's head. He smiled and gave a new command to his Mouser. "So you don't want her hurt, huh? Well then… Just gotta set it to full power and..."


The Mouser turned its head and readied a powerful shot aimed at Hibari. She was too frightened and shocked to do anything. Out of protective instinct, Yagyu jumped in front of Hibari at the last second. This shot was more powerful than before and it blasted Yagyu right onto Hibari. They both fell and a residue of smoke escaped from Yagyu's damaged shirt.


"HA! YES!" Stockman cheered. "Now, we can…" His celebration was cut short when he noticed several shadows from around the corner getting closer. He groaned. "You know what? Screw this! I'm getting out while the getting's good!"


The Mouser found the nearest window and crashed right through it. Immediately after that, the turtles and shinobi arrived and gasped when they saw Yagyu and Hibari on the floor. Hibari was still conscious, but looked stricken with guilt. Yagyu however was unconscious and clearly hurt.

"Hibari, Yagyu, are you all right?" Kiriya asked. "What happened?"

"…It's my fault." Hibari whispered nearly sobbing. "Yagyu's hurt… and it's my fault."