After the temporary blackout, the party mood was gone, so everyone went home. Asgore called Alphys. She apologized and said that the CORE shorted out for a moment. Eventually, the systems managed to reboot themselves. She went to work trying to figure out what went wrong.

During the next several weeks the CORE was unable to go a full day without randomly shutting down. Despite Alphys' best efforts and multiple attempts to replace damaged components, she wasn't able to stop the problem completely. Every time she thought she fixed it the CORE would shut down within a few hours and she would discover yet another damaged component that needed replacing or fixing.

Even worse, the intervals of darkness were getting progressively longer. At first, it would only be a few seconds. Barely time for anything to happen. But slowly, the blackouts were getting longer, lasting several seconds.

Frisk hoped Alphys would eventually fix the CORE and get it back in order. People were starting to complain about the constant blackouts.

But on the positive side, Asriel was adjusting rather nicely to being alive again. He was still incredibly shy, but Frisk was able to get him to socialize more. He also convinced Papyrus to accept Asriel as an employee. Though the Boss Monster was hesitant, Frisk insisted that it would do him good to have a job where he talked to people.

Outside of that, Asriel was becoming more like the kid his parents talked about. Frisk would still see Asriel crying on occasion, wrapping himself in a blanket and sobbing. He knew he still missed Chara and was probably still kicking himself for failing to save them. Frisk knew he had to tell Asriel the truth someday, but he wasn't sure when that would be.

A month later, Frisk was walking with Asriel to Snowdin. Today would be Asriel's first day working for Papyrus.

"I'm still not too sure about this, Frisk," Asriel said.

"You'll do fine," he assured. "All he'll have you do is buss tables and take orders."

"It's not just that. It's the people," Asriel whined.

"Everyone knows who you are, and they'll be respectful. They'll see you're busy," Frisk assured.

Asriel was wringing his hands as they approached the back door of Papyrus'. "Can't you come in with me?" he asked.

"I don't work today. And don't worry, Papyrus is very nice," Frisk promised. He clapped Asriel on his arm. "You'll be fine. Have fun!" With that, Frisk turned and left his brother, and headed further into Snowdin.

Shaking, Asriel opened the door and walked into the kitchen. He saw Papyrus already at work preparing food while Sans passed his brother whatever he needed.

"Um, hi," Asriel said, waving a hand in greeting.

"OH, YOU'RE EARLY! THAT'S GOOD!" Papyrus said. "NOW, IF YOU WOULD BE SO KIND AS TO PUT ON YOUR UNIFORM AND CHECK THE DINING ROOM FOR ANY CRUMBS."

"Uh…"

"changing room's right next to you," Sans informed, pointing to the door Asriel was next to.

Asriel stepped inside and spotted a cubby with his name on it. Folded up inside was his uniform. He pulled it out and put it on. He managed to recall Frisk's instructions on how to tie the bowtie. He looked himself over in the mirror before heading out. He almost couldn't believe he was doing this. But both his parents and Frisk insisted it would be good for him. He just hoped he did everything right.

Frisk continued through Snowdin, arriving at Noelle's house. He knocked on the door and December answered it.

"Oh, hiya Frisk," she greeted.

"Howdy. I'm here for Noelle," Frisk returned.

"She'll be out in a minute. She's still getting dressed," December informed. "Um, if you want you can wait inside."

"Thank you." Frisk walked inside, waiting in the living room. He looked around, noting the changes since he was here last. The picture of Rudy was still on the mantle where it had been ever since the funeral. He still missed him, and he knew Noelle did as well. Time hadn't healed the wound yet, but it did make it hurt less.

After a couple minutes, he heard a door slam from upstairs and Noelle came down the stairs a minute later. She was dressed in her regular sweater and skirt.

"Hi, Frisk," she said.

"Hi," he returned. "Ready?"

Noelle nodded. She turned to her sister. "Tell mom I'll be back later."

"I will. Though I am wondering why you two spend so much time together," December said.

"He's fun to play with," Noelle said, hoping her sister didn't pry.

"That's it? Because you two are together almost every other after-"

Suddenly, the lights went out.

Frisk immediately grabbed Noelle's hand, and she grasped her sister's. They stayed like that for a few seconds, Frisk counting in his head the seconds that passed.

Eventually, the lights came back on.

"Was it just me, or did that seem longer?" December asked, previous conversation forgotten.

"Ten seconds," Frisk said.

"It's never lasted more than eight before," Noelle said. "It's getting worse." She let go of Frisk's hand before her sister saw.

"Hope your scientist friend fixes it before it gets too much worse," December said to Frisk.

"You and me both," he muttered. "Well, on that cheery note, we're off." He walked out the door, Noelle behind him. Once out of earshot he talked. "That was too close."

"What was?" Noelle asked, confused.

"Your sister. She's starting to pry into our relationship," Frisk clarified.

"Oh, right!" Noelle said. "Yeah, that was close."

"Lucky the power failed to distract her."

"Yeah, sure," she said unconvincingly.

"Something wrong?"

"Why are we still doing this, Frisk?" Noelle asked.

"Doing what?"

"Keeping this," she pointed to herself and him, "secret?"

"I thought we both agreed our moms would have a heart attack if they found out," Frisk answered.

"Yeah, but we keep this from everyone. Even our friends." She looked around. "I'm a little tired of the lengths we go to to keep it secret."

"Hey, I'd like to tell the other too, but I don't trust them to keep it secret from our parents," Frisk said.

"You think they'd tell them?"

"I think they'd tell someone and that one would tell someone else, and so on, until the gossip got to our moms," Frisk clarified. "And I'd rather they hear about it from us first than some second- or third-hand accounts."

"Oh. That makes sense." Noelle admitted.

"Maybe when we're both twelve," Frisk said. "Then they wouldn't have much say in who we dated."

"They wouldn't pull us apart, would they?" Noelle questioned.

"Your mom might. I don't know if she would approve of our relationship."

Noelle sighed, unable to come up with a counter. "You've got a point."

"Just a little longer. Then we can tell them," Frisk promised. "Now, shall we head to the forest, my dear?"

She giggled as he held his arm out for her. "We shall, my prince." She wrapped her arm around his as they walked across the bridge into Snowdin's forest.

Asriel wouldn't say he had a great time working for Papyrus, but he wouldn't say it was bad, either.

On the one hand, Papyrus was fair and kind and extraordinarily patient with Asriel. He calmly explained what to do and explained how each item on the menu could be customized. He found it fun, taking people's orders and handing the tickets to Papyrus, who would give him the requested meals to deliver to the customers.

On the other hand, rush hour was the worst. People would file in the door and Asriel would help them find a table, then rush all over trying to take the orders, then get the orders to Papyrus in a timely manner, and then take the finished orders to the proper tables. On top of that, he had to make sure a table was clean after a group finished using it so the next group could be seated quickly.

After the rush, Asriel was exhausted. Papyrus agreed to give him a few minutes to recover before sending him back out to continue.

Luckily, Papyrus had him clock out about midafternoon, as he didn't want to overwhelm Asriel on his first day. He changed back into his more casual clothes before heading to the town square, where he was to meet Frisk after he got off.

Asriel waited patiently, standing in the snow for a few minutes. Eventually, Frisk showed up with Noelle in tow.

"You already got Noelle, cool," he said.

"Yep," Frisk said. "So, how was it?"

"Well… is it always that busy?" Asriel asked.

"During the lunch hour, usually," Frisk answered. "Don't worry, though, you get used to it."

"Well, shall we head on to New Home?" Noelle suggested.

"Let's go," Frisk agreed.

The three of them went to the city together. Noelle asked Asriel about his first day. Frisk let her handle the questions and they both gave Asriel advice on what to do. Once they reached the city, they walked down the street, heading for the park. It would be the first time that Asriel had ever seen it and they were meeting the rest of their friends there.

Noelle was the first to show Asriel around, pointing out the various areas. They went to the playground where they intended to spend the rest of the day. Susie, Berdly and MK wouldn't be there at first, as the three of them still had homework to finish.

Asriel first wanted to go down the slides, so they showed him the tallest one first. As they explored, killing time waiting for the rest of their friends to show, Noelle decided to talk to Frisk while Asriel was climbing up the stairs for the next go.

"Have you told him about Chara yet?" she whispered.

"Not yet," he admitted.

"Well, when are you going to tell him?"

"I don't know. Maybe when he's finished mourning them," he said.

"That could be months," Noelle pointed out. "Are we really going to keep him in the dark that whole time?"

Frisk shrugged. "What else can I do? If I tell him the truth before he's ready, it could destroy him."

Noelle sighed. "I know. I just wish there was an easy way to tell him."

Then they heard Asriel's squeal as he slid down. He landed on the soft ground with a giggle. "Man, this is fun!"

"Glad you like it," Frisk said.

"So, what do you want to do next?" Noelle asked.

"How about those bars over there?" Asriel suggested, pointing to the monkey bars.

"Good idea," Frisk agreed.

"I'm not sure I can climb that," Noelle said.

"That's okay," Frisk said, heading for the bars. "You can watch and make sure we don't fall."

"I guess," Noelle agreed.

Asriel grabbed the first set of bars, preparing to climb, when the lights overhead flickered. He immediately let go just as the lights went out.

"Frisk?" Asriel questioned into the dark.

"Right here. Take my hand."

Asriel reached in the direction he heard Frisk's voice, grabbing hold of Frisk's hand when he found it.

"Noelle?" Asriel asked.

"Right here," she said. "I already have Frisk's hand."

"Don't worry. I'm sure the lights will come back on," Frisk assured.

They stood there, holding hands, waiting for the lights to come back.

And waited.

And waited.

And waited.

Frisk stopped counting the seconds after thirty had passed. "Lights, come back," he muttered.

It was then a light shone, but it wasn't the lights of the Underground. Rather, it was a fireball shot into the air, illuminating the area in a dim white light.

"That can't be good," Noelle said.

"Noelle? That you?" a familiar voice called out.

"MK?" Frisk questioned. "Where are you?"

"Over here!" came Susie's bellow. As the light faded, the two groups caught sight of each other. Susie was holding MK's tail and Berdly's hand. They ran to each other, Asriel taking Berdly's free hand, just as the light from the fireball went out.

"You guys okay?" Berdly asked.

"We're fine," Asriel answered. "Just shaken."

"Something's wrong," Frisk said. "The lights have never been out this long."

"Something must be wrong with the CORE," Noelle deduced.

It was about then that the noise of panicking Monsters reached them. People were starting to freak out at the length of time the lights had been off for.

"We need to go see what's wrong," Frisk decided.

"How do we do that?" Susie asked. "It's pitch black."

Frisk let go of Asriel's hand and conjured a fireball, the red flame illuminating the area. Then he made many more, allowing the group of friends to easily see each other. "This will help. Now don't let go until we get to Hotland."

Together, they ran to the volcanic region of the Underground, navigating their way through the streets and frightened Monsters. Frisk sent a few fireballs to hover in areas they passed so the Monsters could navigate the dark.

Eventually, they got out of the city and into the magma chambers of Hotland. Frisk dispelled the flames as the ambient light from the magma was enough to navigate. Eventually, they reached an area that overlooked the CORE. And what they saw made them stop and gasp in horror.

The CORE was on fire.

A massive pillar of smoke was rising from one of the upper parts, vanishing into the darkness above. They could hear the shouts and screams of CORE workers as they tried to get the blaze under control.

Noelle had her hands covering her mouth, standing completely still as she stared at the column of smoke. Many of the others were staring in slack-jawed fear.

Frisk shook his head to regain his thoughts. "Lab. Hopefully Alphys knows what's going on." He ran on, his friends trailing behind. They got to the lab but encountered their first problem when the doors wouldn't open.

Frisk banged on the doors. "Alphys?" he shouted. He waited a moment before banging again. "Doctor Alphys, it's me! Open up!"

When they still got nothing, Frisk decided to try and force the issue. "Susie?"

Susie punched one hand into the other before stepping up. She grabbed the side of the door that opened and began heaving with all her might. Slowly, she managed to force the door open enough for them to slip through. But when they got into the lab, they found that it was dark as well. Frisk pulled out his phone, turning on the flashlight to illuminate the place. Everyone else did the same, except for Asriel, who did not have his own phone yet. He stuck with his brother as they searched for Alphys.

After several minutes of fruitless looking, they reconvened in the main area. "Where is she?" MK wondered.

"Not here, apparently," Berdly said.

"Perhaps she went to go help fix the CORE," Noelle suggested.

"Good point," Frisk agreed. "But what's taking so long? The power's been out for almost half an hour."

"The CORE was smoking rather big," Susie pointed out. "Something big must've caught fire."

"Guys, could the power… stay off forever?" MK asked, a thread of fear in his voice.

"If it does, we could lose a whole lot of progress," Berdly said. "Most of what we use and depend on uses the power the CORE provides. Without it, we'd be sent back to the dark ages."

"More like the pre-industrial age," Noelle corrected. "But that would be a lot of advancement lost."

"I don't think I could imagine my life without a tv," MK bemoaned.

"And I don't think I could cope without my computer," Berdly said. "How will my gaming channel survive?"

Frisk slapped his forehead at his friend's misplaced priorities. But he could see the point. The Monsters' lives largely depended on electricity, and the CORE was the only source of it they had. Their civilization could collapse without the CORE.

As he was trying to think of ways to adapt, the lights slowly flickered back on. Everyone let out a sigh of relief as the lights came back on. However, they noticed that they weren't as bright as before.

"Thank goodness. They must've fixed it," MK sighed.

"I'm not sure I'd call it 'fixed', given that the lights aren't all the way on," Frisk said. He did notice that the lights were slowly getting brighter, but that wasn't necessarily good.

Just then, everyone's phones dinged or rang from a text or call respectively. Frisk answered his phone, Toriel's worried voice on the other end.

"Frisk! Are you okay?"

"I'm fine," he assured. "We both are."

"Both? Asriel is with you too?" she asked.

"Yeah, he is," Frisk confirmed.

"Oh, thank goodness. I was concerned. Your father and I were worried."

"We're fine. We're at Alphy's lab, trying to find her to see what's wrong," Frisk explained.

"Is she there right now?"

"No. We think she was trying to get the situation with the CORE under control," Frisk said.

"What situation?"

"The CORE was smoking. There was a massive pillar of smoke coming from it."

He heard his mom's sharp intake at that. "Your father and I will be right there."

"But we're fine."

"It is not you we are coming to check on. We will need an explanation from Alphys what happened."

"Okay. Bye, mom."

He hung up, looking around to see the others doing the same.

"So, I guess we just wait here?" Berdly asked.

"That's the best move. My parents know we're here, at least."

"Hope whatever's wrong with the CORE can be fixed," Susie said.

After a few minutes, Asgore and Toriel arrived. They hugged their children, just to reassure themselves that they were alright. They also greeted the other kids. But Alphys still hadn't shown up.

"Where is the doctor?" Toriel wondered.

"She must still be working on the CORE," Asgore assumed.

"I hope she is alright," Toriel said. "We saw that smoke coming from it. The blaze must have been huge. I pray that she is in one piece."

"Mom, calm down," Frisk said. "Alphys is strong. She'll be fine."

Toriel nodded, patting Frisk on the head.

They continued to wait for several more minutes, the lights occasionally flickering. Eventually, the flickering stopped. But it was still another two minutes before Alphys showed up. Though she wasn't alone. A couple paramedics were with her, one wheeling a metal canister, the other helping Alphys walk, as she had a mask on that was connected to the cylinder.

"Doctor!" Asgore and Toriel exclaimed together, rushing to her side.

Alphys coughed into the mask a couple times before taking it off to answer. "Hey," she replied, her voice scratchy.

"Doctor, what happened?" Toriel asked, healing magic ready.

Alphys shoved the hands aside. "Too late for that," she muttered. "Had to stand in a room that was half smoke to get the CORE functional again for several minutes."

"Do you need any assistance?" Asgore asked.

"Just get me to my chair," she said. Frisk was already running over with her desk chair, and Asgore and the paramedic helped her sit down. She coughed into the mask a couple more times.

"Will you be okay?" Frisk asked, his friends gathering around him.

Alphys coughed again before answering. "Yeah. Just need to breath from this mask for a couple hours."

"Doctor, the CORE?" Asgore asked.

"It's ruined," Alphys said. "The damage was worse than we thought."

"What do you mean? You said you were fixing it," Toriel asked.

"It's not working," Alphys bemoaned. "No matter what I do, more systems fail. Today, an entire bank of relays blew, which triggered a chain reaction that caused some of the magma-to-magic converters to ignite. We managed to get them working again, but the damage they caused has ruined too many systems to fix."

"Aren't there any failsafes or redundancies?" Noelle asked. "Who would build something like this and not have a backup?"

"There aren't any," Alphys bemoaned. "Whoever built the CORE decided that redundant systems weren't necessary, so he left them out."

"What does that mean?" Asgore asked.

"It means that eventually, the CORE is going to fail completely. And when it does, I won't be able to fix it," Alphys explained sadly.

"Isn't there anything you can do?" Asriel asked.

Alphys shook her head. "I've been studying the design for months, but the Monster that made it didn't see any need to repair it, so he left those out of the designs. And, um, it gets worse."

"Exactly how does it get worse?" Asgore asked.

"While there is a possibility that the CORE will just completely shut down, there is also a possibility it could… um… explode."

"EXPLODE?" MK shouted.

"I don't know how bad it could get, but if it goes into meltdown, and I can't shut it off, it will take the whole Underground with it. That is the worst-case scenario," Alphys explained.

Everyone gasped at that statement. Frisk reached out and held Noelle's hand, giving it a squeeze as tears shone in her eyes. Asriel buried his face in his hands, crying to himself. Asgore hugged Toriel as she leaned into his embrace.

Frisk was frightened by this possibility. Everything he'd ever known, everything that the Monsters ever built, could all be wiped away, along with the Monster race. As Alphys was tended to by the doctors, Asgore and Toriel escorted their children home, the other kids returning to their homes as well. Along the way, Frisk tried to think about the positives, but he was coming up empty.

Even assuming the best-case scenario, in that the CORE just shut off for good, it would leave the Monster race without power for probably forever. Especially as they had no alternative. He thought Alphys could design a new CORE, but she didn't seem to understand the designs of the present one. Whoever built it didn't share the knowledge of magma-to-magic energy conversion.

When the CORE went, the Underground would probably follow, regardless of whether or not it exploded. One way or another, the Underground would be gone when the CORE finally shut down for good. And the Monsters would vanish with it.

Toriel, her motherly love and comfort, gone.

Asgore, his joyous personality and friendly demeanor, gone.

Asriel, just returned and rediscovering life, gone.

No.

Papyrus, his restaurant, his popularity and great Italian cuisine, gone.

Sans, his puns and brotherly affection, gone.

Undyne, her energy and drive, gone.

Alphys, her brilliance and friendship, gone.

No!

MK's energy and friendliness, gone.

Berdly's nerdiness but enjoyable company, gone.

Susie, her rough attitude but soft inside, gone.

Noelle, gone.

No! I won't let that happen. I refuse. I won't let everyone die.

We can't fix the CORE, but the Underground isn't the only place to live.

If we can't live down here anymore, then it's time to go to the Surface.

End of Chapter 23