"Alright, so explain it a bit more slowly this time," Yang sighed.
"Right, right. It came to me while watching you train. Penny could theoretically run without her own aura, as long as she is able to draw from an active one. Now normally the draw would be enough to place a serious strain on the aura donor. The key here is your rather unique emblance. I watched your power rapidly increase as your aura absorbed damage. Furthermore, that radiation you put off while your semblance was active suggests that you have a far greater aura than the average hunter. I believe that with proper calibration you could supply Penny with aura without it draining your own too heavily. On top of that, if done properly her aura leaching may also result in a constant base charge for your semblance. Of course there are risks. A cybernetic on its own takes weeks if not months to adjust to, and your body will initially try to reject it. The aura drain will only exacerbate it. All said though, the positives for both parties far outweigh the risks in my opinion. But my opinion has little weight here, you need to decide if you want it." The doctor prepared to give Yang a moment, but she didn't need it.
" So what do we need to get started?" The doctor was somewhat shocked with how easy it had been.
"Are you sure? Even if everything goes according to plan, you will have another sentience for the foreseeable future. While I would obviously want it to happen, you need to be sure you're ready for that responsibility?
"I've never been more sure of anything doc," Yang said with confidence. For the first time in months she was smiling. " I can take anything you throw at me, and the arm is just a bonus if it means getting Penny back. I didn't know your daughter that well, but I know it would make everything a little better if she were around again." The doctor smiled his first genuine smile in a while.
"Let's get started then." With that, Marcin typed a quick pass code into his scroll. He waited a few seconds, still smiling, before he heard a dull thud emanate from the backyard. It was time to get to work.
Yang had initially been peeved when the doctor decided to park his rocket lab in the backyard. It had ended up tearing a massive rut where it landed. However, the backyard wasn't used for all that much and in the end this was all worth a lot more than an ugly lawn. Over the following week, the doctor took careful measures of her aura output and had begun to craft dummy arms for her to test. It had taken her four days to stop throwing up after the first one was installed. When she finally got her feet back under her, she managed to completely ruin the arm with three solid punches. Yang had torn the mangled limb off, leaving only the joint connector on her stub. The doctor had been apologetic, saying that he had not anticipated that she would be able to apply that much force. However, the starter limb had done its purpose and accustomed Yang to having a foreign object connected to her nervous system. After the doctor had made brief repairs to the joint connector, he gave her another spare arm to wear until he could build her one out of stronger material. Yang busied herself with speed training while the doctor worked. For the first time in awhile she was rearing to get back into the thick of things, and this time she was going to be ready. Weeks passed as the doctor attempted to build a housing capable of holding Penny as well as withstanding Yang's immense strength. It was a delicate balance, there needed to be enough space Penny without sacrificing structural integrity. Finally one early morning, the doctor left his lab and approached the house. Yang returned from a morning run to find him sitting at the kitchen table, positively giddy.
"I think I have it Yang!" He practically yelled as she walked in the door. "I'd be shocked if even an Atlesian heavy artillery could do more than scratch this beauty," The doctor gestured to the device on the table. "It's as much a work of art as it is a scientific breakthrough, if I do say so myself." The good doctor wasn't wrong. The arm was mostly white with green highlights and a black fist. It was far sleeker than the arm Yang was currently wearing. There were several indicators across the surface that Yang assumed she would eventually be told the purpose of. Looking closely, she saw a hairline seam tracing an odd design in the center of the arm. On closer inspection, there were two more identical tracings evenly spaced around the forearm.
"What are these?" Yang asked as she fruitlessly picked at the seam with her fingernail.
"Those, Ms. Xiao Long, are my daughters weapon of choice," Dr. Marcin said proudly. With a quick command from his scroll, the doctor unhoused three daggers from the forearm. Each was connected with a silvery strand of wire that could only be seen on very close inspection. " They're an experimental Atlesian alloy, it never dulls. Perhaps your strength could break them, but barring you making a concerted effort to do so they will never fail. They can also serve as conduits for an aura cannon. With your sizeable aura reserves, even this smaller version will be incredibly formidable. You should be warned though, this isn't a weapon you should use lightly. Even one shot will result in a significant drain on your aura. The blades on their own are formidable and versatile, only use the cannon in the most dire of situations. But we are getting ahead of ourselves. Go ahead and try it on, see how it feels." Yang was slow to process his words, as she was still admiring the machine in front of her. Once she did, she unceremoniously disconnected her trainer arm and reverently picked up the new limb. She quickly connected it, and immediately knew it was right. She brought her fists forcefully together, and was delighted to feel pain in her real knuckles.
"Let's see what this thing can do!" With that, Yang sprinted from the room out into the back. Before the doctor had even gotten out of his seat, he heard the splintering of a tree. When he walked out, he was greeted with Yang completely flattening her old dueling platform. Yang didn't even let the dust settle before running off into the woods. The doctor smiled and returned to the house to wait. Several hours later, Yang walked back in red faced and grinning ear to ear.
"This thing is amazing! I never saw it so much as flex wrong, even when I punched through a boulder."
"So you like it?" The doctor asked, already knowing the answer.
"It's perfect."
"Excellent. Then there is only one thing left to do. I'll install Penny tonight, and we will see if this will work tomorrow morning." Yang reluctantly removed the arm and handed it back to the doctor. She knew she was too excited to sleep. As the doctor wandered back to his lab to make final preparations, Yang sat down and prepared to anxiously wait for eight hours.
Yang awoke with a start, drool sticking her face to the dining room table. The morning light was bright in her eyes. Yang adjusted slightly and tried to go back to sleep before sitting bolt upright. It was morning. It was time. Yang walked as calmly as she could to the door of the lab and knocked.
"Dr. Marcin? May I come in?"
"Of course child, I've been waiting. She is ready." Yang didn't need to be told twice. She darted into the lab and saw the arm... Penny now... set delicately on a stand for easy access. " I wanted to make sure you were well rested Yang. I know you are excited, but this first aura drain will undoubtedly be the most difficult. After this she should draw a manageable amount, but the amount needed to jumpstart everything will be fairly large. Are you ready?" Yang's face turned sober and determined.
"I'm ready doc. Let's do this"
"Alright, give me your connector and I'll attach her." Yang extended her stump towards the doctor. He delicately aligned Penny to the various connectors and attached them in quick succession. He sent a command through his scroll, and the arm began to activate. Yang knees nearly buckled under her. Her eyes were narrowed to dark funnels. A second wave pushed her to one knee. Her breath came in short bursts, and her entire right side began to go numb. Then, as quickly as it came, the feeling was gone.
"Did it work?" Yang managed to sputter as she caught her breath.
" SALUTATIONS!"