"The mission to seize the petrifaction beam begins in earnest near. And our key to success this time will be the earrings of science," Senku stated.
"Oh ok, and what are those," Gen asked.
"Are we trying to make someone extra cute now or what," Soyuz asked.
"What's the point? They already started the selection," Suika said.
"That's why I'm whippen this up at top speed," Senku said. He chuckled. "We're lucky the copper wire looks the way it does. It might seem like decoration when really it's a conductor."
Senku used your ear to model the hook of the earring that goes around the ear. On the hook he attached Rochelle Salt from wine which is what you guys used for the speaker. So with Rochelle Salt sound transmitting crystal and a copper wire antenna as an earring, you guys have yourselves an earpiece. After it was down, you guys went off to secretly deliver it to Kohaku.
"I keep looking but I can't seem to find any machinery on this thing," Gen said as he examined the earring. "Does this bit in the middle pick up radio waves or what?"
"Yeah," Senku confirmed.
"It's so tiny," Gen exclaimed. "You must've made a microchip when I wasn't paying attention."
"No it's just a rock," Senku said.
"Eriously-say," Gen exclaimed shocked.
"Different kinds of rocks can get the job done," you stated. "Just use Galena, Pyrit or native copper and they'll do the trick. Plus it doesn't matter if it tiny as long as it gets the job done, the size shouldn't matter that much."
"Interesting choice of words y/n-chan," Gen said as he went back to examine the earring. "And where's the battery?"
"You don't need one. Thing will work forever without it," Senku stated.
"Eriously-say," Gen exclaimed shocked.
When you guys docked, you guys spirited to where the girls and guard would be passing by. Due to your injury, Senku and Soyuz carry you as you guys run like hell uphill. On the way Gen, still being confused by the earring, asked how it could work if it didn't have a power source. So Senku breathlessly explained that the earring is gonna work like the old timey crystal radios. The sound is faint but it's no problem if it's directly in your ear.
You guys made it to the area to see that all three were chosen. You guys shared a quick laugh that 'Miss' Ginro made it through but you guys went back to work mode. Soyuz threw the earring to Kohaku, who thankfully noticed it and caught it.

Senku chuckled as he got the phone ready. "Didn't have time to test this thing for real so it's gonna be do or die."
"Can you hear me Kohaku," Gen asked through the speaker. "If you can give me a signal like..." Gen began to think until he got a cheeky grin. "Strike a cute pose for us."
You guys see Kohaku visibly struggle and panic as she thinks of a pose. Her body was so stiff until she managed to strike the pose Suika usually does with a cute face to match. Gen laughs as the rest of you are just glad the earpiece works. Gen gets a shiver down his spine as you guys bet that Kohaku just threatened him even though you guys can't actually hear her.
"So now that we give Kohaku instructions through the earpiece what's are actual strategy for getting our hands on petrifaction beam," Suika asked.
"The only person we know who has one is that warrior y/n and Kohaku fought, Kirisame," Senku said.
"Yeah and we're judging by that fight. She's ridiculously strong," Soyuz said as he got scared.
"Yeah. Which means we can't just try to run up to her and steal it since that will just cause trouble," you stated. "Not to mention, it's clear that she's aware of how valuable that beam is and when you have something valuable, you don't want it to fall into the wrong hands. So we have to steal it when she let's it go and I have a feeling there's only one moment when she lets it go."
Everyone but Senku was confused by what you meant until Gen thought about it. He got a nervous reaction as he came up with an answer.
"When she throws it to use it, you mean. Like when it's in the air," Gen said.
"That's our chance to strike," Senku said.
This made Gen worried as he didn't even know how you guys could do that. But right now, you guys had to tell Kohaku the plan. You guys were in two teams, the science team and the spy team. And the spy team's first job is to observe closely and when Kirisame is alone, lure her to a secluded spot. Then get her to throw her weapon and once they do that, the science team will nab it in the air and for that, you guys are making a drone.
"I'm not an expert on the topic but don't drones float perfectly blanched with no input from the user? We need a control system for that. Like one with circuitry and microchips," Gen said.
"You have a point Gen but do you really think Senku would have proposed this idea without a plane," you asked rhetorically.
"Then what is this plan," Gen asked.
"What we should focus on now is making a motor," Senku said.
Using a bracket, Senku was going to wrap some copper wire around iron. Then run electricity through it and you get an electromagnet. Now doing the same thing but with two magnets, they repel each other which causes them to spin around. And since it would take Senku all day if he did it by himself, you all got to help him make the electromagnets by wrapping wires hundreds of thousands of times. This manual labor brought tears to Gen's eyes as you sat in the lab. Due to the injury, Senku is keeping you from doing too much work until the wound heals.
You sighed as you leaned your head against the wall. You gently placed your hand on your stomach as honestly at that moment felt useless. While the others did their parts, you were just sitting there. While the others were doing what they could to save your friends, you had to sit down and wait for your dumb injury to heal. It frustrated you but you had to keep your cool since if you got too emotional, that'll put stress on your body which could open your injury. But all you could think about was your petrified friends. Taiju... Ryusui... Nikki... Yuzuriha... Chrome... Ukyo...
*Flashback*
You were breathing heavily as you leaned down against one of the parole bars.
"I never thought this was gonna be so hard," you huffed.
"He-He. I don't think I've ever seen you this tired ever."
You turned your head to see Ukyo looking at you. You were a bit confused and was about to say something but your legs gave out and you nearly collapsed. But you managed to maintain your grip on the bar and kept yourselves from falling. Ukyo helps you stand and brings you to a chair and helps you sit down.
"Thanks," you said breathlessly.
"No problem," Ukyo said.
"So... Did you want to talk about something or did you just come to say hi," you asked.
"Yeah. I um, I did have something I wanted to talk to you about," Ukyo admitted as he rubbed the back of his neck.
"Well, what is it," you asked.
Ukyo cleared his throat as he was having a bit of trouble finding the words. You could tell from his expression that he doesn't know what to say. You simply sat and waited for him to speak. After a few seconds he managed to say something.
"I'm sorry," Ukyo said.
"For what exactly," you asked.
"For everything," Ukyo admitted. "I'm sorry for capturing you and not trying to help you when Tsukasa interrogated you. I'm sorry that I couldn't protect you from Hyoga or help you when you had a panic attack. But I'm really sorry I left in the first place."
"Whoa... That's um, that's a lot to be sorry for," you said with a little chuckle. Your eyes then softer as you look at your hands. "Why did you leave in the first place?"
"Because y/n, you and I have a 4+ year age gap. Naturally that alone was gonna get in the way of our friendship," Ukyo said. "I went to work in the submarine and I didn't know when I was gonna come back while you were still in high school."
"No, I get that Ukyo," you stated. "But... why didn't you say anything? Why did you just disappear? I mean, you could've said bye."
"I know, I was in the wrong for that but I did it to protect you," Ukyo said.
"Protect me," you said, a bit confused.
Ukyo sighed. "Y/n, your parents might have gotten Hyoga to leave you alone but they did get rid of him. About two days before I left, I was cornered by Hyoga and he told me if I don't leave you alone, then he'll kill my family and yours. I didn't want to believe him but the next day after we talked, he sent me a video of him, stalking my parents stating that if I don't leave you they'll be dead. So that's why I left. "
Your eyes widened at this confession. Either Hyoga really wanted you to be his soldier or he was simply pissed that by what your parents did that he was determined to destroy your lives. Regardless of the reason, it made you upset.
"Is that really what happened," you asked.
"Yeah...I'm sorry I never told you but I didn't want to risk anyone dying," Ukyo said. He sniffled a bit as he teared up a bit.
You put your hand on his arm trying to comfort him. "It's not your fault. Hyoga is a dangerous asshole and you were just doing what you thought was right to protect everyone. But I'm just glad that you told me."
You two shared a little hug as Ukyo tried to compose himself. It was nice to finally know the truth and you felt like you finally had your friend back. After so long, Ukyo finally came back and he'll definitely be a key player to bring back humanity.
*Present time*
"Y/n! Check out what we made," Suika exclaimed.
You snap back to reality and peek out the lab to see what was going on. You saw Senku putting down a little contraption. It was a bamboo frame with four plastic propellers and electromagnetically powered motors controlled by radio signals. This little radio controlled car gave Gen an idea and gave the motor a little design.
You guys made the radio controlled car look like a rat and sent it to Kohaku since it can also be used for communication. And thanks to its chaotic movements, the car looks more like a rat and if the spy team was in trouble they could use the rat to send an SOS message.
After a while, Suika came back to give you guys the rat-bot to find a pink cloth. You guys take out to find a confusing drawing.
"What's this mean," Soyuz asked'
"Is it a code? It's like a game show's final puzzle," Senku said.
"I didn't think about it but that's probably the best any of them can do. You know, considering they can't write at all," Gen said.
"Now I really wish I was there. It would have made this ten billion times easier," you sighed.
"You're right y/n-chan but there's no point in sulking in the past," Gen stated. "Right now, we have to decipher the intended message. Here's the thing, the trick is to put yourself in the mind of the writer."
Senku tries to do that but he really makes out what the message means. He guessed the message was 'An ice pop that Hyoga has got melted by an engine,' which horrified Gen and just frustrated Senku.
"I guess for how smart you are, you never did like these kinds of things," you said.
"You wanna give it a try y/n-chan," Gen asked.
"Sure," you said.
Senku gave you the cloth and you look at the pictures.
"You know, it'll help if you think about what was going on in the person's mind when they chose the picture. Usually when people draw pictograms, they want to make it as simple as they can to get the message across," Gen said.
"Okay but these pictures are pretty confusing. So that just tells me they could make it any simpler," you said.
"Exactly. Which means the word they want to say is most likely unfamiliar to them," Gen said. "So perhaps they used science terms."
"Well I guess that makes sense," you admitted. "After all, how the hell would they know what an ice pop is in the first place? And if it's a scientific item then...maybe plastic."
"So does that mean? Those three want us to send them plastic," Suika asked.
"I don't think so. What use would plastic be in their situation," Senku said.
"It could be an acronym," you said.
"You have a point y/n-chan. So let's think about it," Gen said. "Next up is a splash which has a specific shape, almost like a tinder to fire. Hyoga is mostly representing his spear which could represent something like fear or strength. But then again, this letter is most likely from Kohaku so it could mean nuisance. And finally an engine, or so it looks but Kohaku might not remember what every invention looks like, it could be a furnace or refrigerator. So with that in mind perhaps it's more generic like a machine, which is my bet."
Senku chuckled. "I've never seen a riddle solved with such brutal force before."
"Wow, I can never do that. It's like he's reading their minds or something," Suika said as she shaked.
"Okay. So if we're taking the first few letters from each word then we have a roughly 90 + possible combination," you said.
"Think you can do it y/n-chan," Gen asked.
"Of course she can," Senku said. "Just watch her."
You begin to think as you mixed and matched the letters and syllabus to try and make a familiar word. It took you a while but eventually you deduced a sentence; "We found platinum", confirming the Soyuz capsule is inside the citadel.
"The spy team found the gift Byakuya left for us," you exclaimed.
"There's only one thing you can mean by that," Gen said.
Senku chuckled. "Our platinum. With that we can relive them all. Every member of the Kingdom of Science."