Expecting Lila's excitement, Aira prepared breakfast early in the morning so that it would be ready right when her companion woke up. Lila came out of her quarters, almost jumping with excitement. "So, are we ready for the test?"

With gestures, Aira invited her to the kitchen and passed her a note: "I really hope it works out. If it isn't, we'll have to find other ways to secure the area. And this may be tricky."

After breakfast, two women left the kitchen and went to the room they designated as their battery bank.

"Alrighty, it's the moment of truth," Lila said, her voice tinged with nervous excitement. "Let's see if all this sweat was worth it—or if we're stuck in sap again."

Aira flipped the switch, and momentarily, the machinery started to hum faintly as the batteries began to fill with the energy. Aira felt a strange sensation unlike any old magic she had ever experienced: thanks to her Energy Manipulation skill, she perceived the currents flowing through the power lines. But this feeling was also new compared to her recent experiences with gadgets. Before, she only had a chance to feel the smaller circuits of those devices. And this was so much more intense.

The first thing Aira and Lila did was charge their gadgets from a tech power source for the first time since they left Mountain View. Before, they had to rely solely on Aira's Energy Manipulation skill, using it sparingly to not overtax her. And now, with a stable energy source at their disposal, the companions felt a renewed sense of purpose and excitement. The possibilities seemed endless. They planned to start with the security measures for the bunker, but their next priority was improving communication. There was something Aira found in the ancient books that she was excited to test.

However, it seemed that Lila had other priorities. After taking a brief moment to ensure everything worked as intended, she grabbed Aira's hand and walked her back to the bunker entrance. The journey was a bit awkward, as Aira didn't have an opportunity to ask what was happening and Lila didn't hurry to explain herself.

When they reached the massive door, Lila placed the undead woman directly in front of it and stepped back to stand nearby expectantly.

Finally, not being dragged in an unknown direction, Aira had a chance to scribble something in her journal and show it to Lila: "What?!?"

"But why," said Lila. "Didn't we do all of that so that we could secure this door? And not suck every single bit of power out of you every time we needed to open or close the door?"

Aira issued a short growl as she wanted to try something else and didn't see the necessity of trying the door right away. In the weeks they spent here, no one came even close to the passageway that led to the bunker. In the end, she shook her head in agreement. If that made Lila happier, Aira was glad to oblige. Both of them struggled with loss in their own way. While Aira had lost her old world a bit earlier than Lila lost her human community, she could relate. And this step would bring a sense of visible achievement and progress.

Deciphering how the control system of the ancient people worked for this door was a challenge. But Aira was sure she'd be able to tap into her first experience when she entered the bunker to operate it to open and close. That should be enough for now, until they split with Lila. If they ever had to split.

Aira used her Energy Manipulation skill and started to trace the circuits that connected the door to their newly operational energy system. She could feel the power spreading, streaming down from the solar panel on the roof. From here, she could feel the storage they crafted, gradually filled by this energy. And the tendrils of power that spread in different directions, including this door.

She tapped into these energy streams, envisioning the door closing. Aira remembered her sensations from the second day at the ancient facility and tried to backtrack the steps she made to open the door. Only this time without overtaxing herself and draining her personal reserves.

But there wasn't even a single reason to worry. The energy they provided for the bunker was enough. More than enough. A moment passed, then another. Lila expectantly watched Aira, who entirely focused on the process. Aira could see that the human was barely keeping herself restrained not to start asking questions and prompting Aira to move faster.

Then, the door started moving, closing the gap in the passageway and rolling slowly on the tracks built into the floor. A few moments later, with a soft bang, it finished the motion and got to its initial position as if Aira had never even opened it.

Lila jumped a few times out of excitement and clapped her hands enthusiastically. "Elder's beard!" she exclaimed. "Aira, you are the best! I feel like we've locked this place tighter than a squirrel's stash."

Aira nodded and focused on the power reserves of their bunker. She still preferred not to use her own reserves, and if the batteries were already empty, she'd wait a bit until they charged. Luckily, her skill allowed her to sense the state of the batteries from this distance. They drained a bit, but it should be fine if the energy spent on opening the door was similar to what was spent on closing the opening.

Once again, she recounted how and which circuits she influenced just moments ago, and the door started its opening movement.

In the end, as they had already tested everything, Aira decided to keep the door closed. Better safe than sorry. The fact that no one came here in the previous weeks didn't mean that someone wouldn't stumble upon this place tomorrow.

Aira took her journal and wrote. "Let's keep it closed. Safer this way. But before we do anything else, there was something I wanted to try with you."

***

"So, what is it?" asked Lila when they entered the room they assigned for tinkering with tech.

The narrative has been stolen; if detected on Amazon, report the infringement.

"Do you remember on one of the first days, you showed me an item you called 'headphones '?" wrote Aira.

"Not really... "said Lila. "There were tons of things we found during the first days here. There may have been some headphones among them. Not that we have ever had any chance to use them. Why? "

"As you know, I've been reading a lot," wrote Aira. "Not only about the things related to charging batteries and generating power. I have a lot of spare time, so I started digging deeper. Learning the things the ancient humans knew about this world and its mechanics. It's almost like learning a magic system!"

"So, what did you find?" asked Lila.

Aira quickly scribbled another note and handed it to Lila: "Here, pick up this pair of headphones."

Lila's eyes lit up with curiosity. "You think you can make these work? What would you connect them to?" she asked, grabbing a set of headphones from the workbench.

Aira nodded and smiled with encouragement. She focused her powers on the headphones, sending pulses of energy toward them, attempting to modulate the signal in a way that would allow Lila to hear at least something.

However, her initial attempt resulted only in a small jolt of energy, shocking Lila's ear.

"Ow!" Lila exclaimed, pulling the headphones off quickly. "What was that? That was uncalled for!"

Aira's eyes widened in alarm, but then she saw the confused look on Lila's face turn into a smile, and both burst into laughter. She gestured to Lila that it wasn't the end of the experiment.

"Well, that obviously didn't go as planned," Lila said, rubbing her ear. "But there is some effect, unlike the last time you tried your powers on me. Still, unless you wanted to electrify me, it isn't really helpful. So, what was your original plan?"

At that, Aira stood up and went to bring several books. Most of them were dedicated to broadcasting information long distance through the air. "They called it 'radio. 'All of that is just different forms of energy manipulation. Should be right up my alley. I just need to fine-tune it," she wrote in her journal.

"Ah," Lila replied, "so you think you can influence these radio... waves? But to what ends? You are right, it all sounds like magic to me!"

"To what ends?" Aira answered. "To talk to you, of course."

Despite the initial unpleasant experience, Lila was excited to finally have some progress in that matter. She promptly offered any help she could provide. Finally, having an opportunity for two-way voice communication would be a game-changer for the two women. However, after the first accident with shocking Lila, Aira was considering which approach to take.

"So, what about using radio receivers?" Lila said. "Remember, besides out standard wristbands, some rangers use them for distant communication. Maybe it will work in a similar way? I brought one from Mountain View, but we also found several of them right here in the facility."

It was Lila's turn to bring stuff to the table. She went out to the next room and returned with a portable radio.

"Here, try this one, I found it among other things in a storage room nearby," she said. "I wouldn't give you mine, at least for now. It's working just fine and I don't want it to be fried."

The device was battered and dusty but seemed to be in decent condition. Lila handed the gadget to Aira, who examined it closely. Her mind was already working on channeling energy into the device without causing any accidental shocks. She sent a few pulses within the small box to probe what was hidden inside and trace its internal pathways. But it needed a more focused approach.

So, Aira took the ancient radio, found a cozy corner, and started her standard meditation routine. Somehow, it was easier to focus on this device here, in the very heart of the facility. All the background noise of plants and living beings was muted, and she could feel each electrical pathway of the device.

Something was missing there, though.

Since the first time she held this world's tech in her hands, Aira felt some special connection with it. When Elder Jorin gave her that fateful tablet, that link was very feeble. But she sensed it nevertheless. But not with this small gadget. She felt that she could influence its circuits with her Energy Manipulation skill, but that was it. No connection to the System.

Still, she continued her meditation. That was a mystery to be solved on a different day. Now, they had to figure out communication. Focusing on manipulating energy in specific ways, she tried to make the radio receive a signal.

"Here goes nothing," Aira thought, directing a controlled flow of energy into the device, careful to modulate the currents inside so as not to overload it.

The radio crackled to life, static filling the air. It was working, albeit imperfectly. Aira extended her powers even more to modulate the signal. The pattern of static changed, but nothing discernible came out of the small box.

Lila watched with an open mouth as Aira continued to experiment. "You'd think I'd stop being surprised by your tricks, but roots and rivers, today's not that day," she said, and then added thoughtfully. "Let me give the radio a try. Maybe my chatter will help you untangle that bramble patch."

She grabbed her own portable radio and started describing to Aira the chain of events that led them to the ancient facility. Lila started with the first encounter in the forest, continuing to tell the story of their journey day after day. Aira smiled and focused on her senses. As it was in her past life with Mana Manipulation, she began isolating patterns and similarities, trying to replicate how Lila's voice was interpreted by the device.

Finally, during one of the pauses in Lila's story, the radio spoke back to her with her own voice: "...you electrified Garrick and we had to leave the town..." repeating what Lila said moments ago.

Lila's eyes widened with amazement. "By the twisted branches, you actually did it! That's sharper than any forest wit I've seen. Though, gotta say, it's a bit uncanny hearing my own voice. Maybe next time, pick a voice that doesn't make me sound so mossy."

A bit more experimentation allowed Aira to modulate the signal so that Lila's words sounded with Aira's voice. At least as what she thought her voice sounded like before the transformation.

Now, only one step was left before finally having a proper communication channel. And then, Aira's question went through: "Can you hear me, Lila?"

Of course, Lila could. Aira herself was hearing her own voice coming out of the small box loud and clear.

They spent the next few hours practicing with the radios, fine-tuning their communication, and experimenting with different frequencies and settings. The process was slow and required a lot of trial and error, but they were making progress. By the end of the day, they had a functional communication system in place. It wasn't perfect, and there were still many kinks to work out, but it was a significant step forward.

Finally, after months of being silenced by the System or some other occult powers, Aira had her voice back.

As they sat together, exhausted but elated, Lila turned to Aira with a thoughtful expression. "You know, this changes everything. We can coordinate our efforts better, explore more efficiently, and keep each other safe even when we have to split."

Aira nodded, her mind racing with the possibilities. She reached out to take Lila's hand in a silent gesture of gratitude and solidarity. Lila squeezed her hand in return and then took out her own portable radio once again.

"Here, take this one," Lila said. "Now I'm sure you've got the grit to keep it working. I'd like you to experiment with it as well."

But the moment Aira got the device in her hands, it spoke in an unfamiliar voice.