Frisk focused his mind while holding his bow to his violin as he did before, but he found no music was coming out. He lowered his instrument and shut his eyes to focus better as Papyrus and Undyne made their way out of the maze.
"Hey, punk!" Undyne yelled noticing Frisk slumping from his perch on top of Papyrus' shoulders. "Are you alright?"
"Yeah," Papyrus said. "I thought you were going to play us a song."
"I want to," Frisk said sadly. "But I can't remember a single song. I don't get it. I remembered a song my mother taught me when I was at the instrument shop. Why on earth can't I remember anything now?"
"Have you tried using your determination?" Undyne suggested.
"That's just it," Frisk replied. "I know my determination had something to do with me remembering that piece before, but I don't know how I got it to work. I can never remember that either."
"Well, that's okay," Papyrus said comfortingly. "Maybe you'll remember later…"
"No way," Undyne interrupted. "That's not giving up I hear. Is it, punk?"
"Well," Frisk stammered.
"What did I say earlier about dealing with your weaknesses, Frisk?" Undyne interrupted again. "You have to face them head on until they're no longer scary. Now, punk, you're gonna sit up there until you remember what you did last time to get your determination to work! You got it, mister?!"
"Yes, ma'am," Frisk replied with a smile. "Okay, what did I do last time? Hey! I remember. I was thinking about my mother and remembering all the good times I had with her and somehow that made me remember a song she taught me."
"Awww!" Papyrus gushed. "That's so sweet. You must have been so happy."
"I was," Frisk said with a bigger smile. "Ever since I've been getting better, my memories have been getting stronger and the happier I get the more clearly I can remember certain things. I remembered that short piece when I played Undyne's piano and earlier I remembered another song my mother taught me."
"I think you're onto something, punk," Undyne said.
"What do you mean?" Papyrus asked.
"Let Frisk figure it out for himself," Undyne replied. "What do all those incidents have in common, Frisk?"
Frisk sat down and thought for a minute before he could realize what all those incidents had in common. Every time he sat down to play, Frisk remembered his mother. Whenever he remembered his mother, Frisk felt truly happy. Whenever Frisk felt truly happy, he could play. That could only mean one thing…
"My emotions," Frisk said in realization. "My memories are connected to my emotions! That's how I can use determination to access my memories! It's like my Dad said. Determination doesn't work unless I put my heart in it. That's why I can only play when I'm really feeling it."
"Oh," Papyrus said. "That actually makes a lot of sense."
"Yeah," Undyne said. "And because you have magic blood that flows through your brain and carries memories within it."
"That, too," Papyrus replied.
"Now, punk," Undyne said. "I know using your magic ain't easy. I had to work like hell to control mine…"
"Really?" Papyrus interrupted. "I thought you were always a badass."
"Nope," Undyne replied. "As I've told you, it takes work to be this awesome. Anyways…Frisk, accessing your memories with determination sounds extremely useful, and now that we've figured out how to do it, I want you to test it out. Use your determination to play a song, but not just any song, try to summon the longest song you know…"
"Undyne, isn't that a bit much?" Papyrus protested.
"Of course not!" Undyne retorted. "When it comes to using your talents, you need to push yourself as hard as you can and then push harder. That is how you become a badass, real Papyrus."
"Oooh," Papyrus muttered in admiration. "You're so cool Undyne."
"I know," Undyne replied proudly. "Now, Frisk, are you ready to make yourself a badass?"
"Yes," Frisk said quietly with a smile.
"What kind of reply is that, punk?!" Undyne yelled.
"Ma'am, yes, ma'am!" Frisk yelled.
"That's better," Undyne said. "Now, focus."
Frisk closed his eyes and used his newfound determination to sort through the happy memories of himself with his mother. To his surprise, memories started returning to him in waves. Every lesson Frisk had with his mother, every song she taught him, all the time they spent playing together flooded his mind with their images. It was so overwhelming that Frisk opened his and found himself gasping for air.
"Frisk?" Papyrus asked in concern while stopping in his tracks. "Frisk, are you okay?"
"Oh, God," Frisk said happily. "I can remember. I remember it all now. You guys were right. The memories were always there. I just couldn't access them, but now, I see all of them."
"That's great, punk," Undyne said. "Did you find a song?"
"Uh, not yet," Frisk said. "I'm sorry. I was so overwhelmed by all the memories…"
"That's okay, Frisk," Undyne interrupted in a tone that was unusually calm for her as she looked back at him. "I get it. Your power is overwhelming and amazing, but you need to bend it to your will. You can't let anything scare you. Remember? Now, dive into those memories and pull out a song, preferably a long one. Okay?"
"Ooh, and make it one about skeletons," Papyrus said happily.
His words instantly brought a memory to Frisk's mind of a song that was just perfect.
"I've got one," Frisk said excitedly. "It's called 'Danse Macabre.' Have you heard of it?"
"No, but it has the 'macabre' in it," Undyne said happily. "I'm pretty sure I'll like it."
"No," Papyrus said. "What's it about? Is it about skeletons?"
"Oh, yeah," Frisk explained excitedly. "It's a song that skeletons used to play every Halloween night on the surface."
"What?"
"Call Sans. I want to explain it to him, too."
Papyrus called Sans and said, "Hey, Sans! Yeah, everything is fine, but Frisk wanted to talk about a song he wanted to play on the violin. He remembered because he used his determination. Listen."
Before Sans could ask any questions on his end, Papyrus put him on speaker and Frisk started explaining, "Before humans and monsters went to war, skeletons would host a large festival every year on Halloween night. Humans and other monsters came along too, and the festival would last until morning on the next day. In the evening, there would be a feast where everyone at all they wanted. Then, at the stroke of midnight, the best skeleton violinist would take his place on a podium above the crowd and summon everyone to dance…"
Frisk picked at his violin 12 times. It sounded like the gong of a clock. The noise stirred memories in Papyrus and in Sans who sat awestruck at the other end of the line.
"The other accompanying violins would come over to support him, but he or she would always be the one they followed," Frisk said moving his bow over the strings and strumming a low tone before swinging his legs over Papyrus' head and sliding down off his back. "Then, everyone would start to dance."
"Stay between us," Undyne chided as Frisk's bow played its first dramatic chords.
Frisk didn't reply, and neither did Papyrus as the music began playing more rapidly out of Frisk's violin. With his rushing memories, his fingers moved steadily and more energetically over the piece he and his mother worked so hard on.
The boy, the skeletons, and Undyne quickly became transfixed by the macabre music that began to grow and swell more and more loudly.
"I've heard this song before," Papyrus said.
"I have, too," Sans said in realization. "Dad used to play this. He used to play for us on Halloween. Do you remember that, Pap? He said it was part of some kind of traditional festival."
"I remember that!" Papyrus exclaimed. "I remember that, too."
Frisk smiled as he began playing the vibrant chorus and said, "Camille Saint-Saens is the one who published the music. His father played this song with the skeletons and passed the music on to him when the skeletons went underground so that no one would ever forget it."
"That's amazing," Papyrus said.
"If you think this sounds good, you should hear the second part that accompanies it or hear it in an orchestra," Frisk replied as he began playing the faster part of the melody. "It's one of the greatest symphonic poems ever made, but I wish I could have seen it in a festival. There, the musicians played and the people danced until dawn while they mingled with the spirits of the dead."
"That sounds epic," Undyne said. "It also sounds like a good place to take someone on a first…Uh, you know what? Forget I said anything."
Fortunately for Undyne, that was easy to do. Frisk and Papyrus were letting themselves get lost in the music from his violin.
Frisk played the song almost effortlessly with all its highs and lows and different tones and sang the accompanying melody when his violin was not playing its solo. The macabre music flowed vibrantly from his fingertips as he reveled in every memory that this song brought to his mind.
Sans and Papyrus reveled in long-forgotten memories of their own.
Papyrus started singing the second part and dancing around Frisk to the melody like he would when his father played. Frisk smiled and started dancing around him, too. Each one copied the other one's moves while adding their own flair. Papyrus performed Frisk's moves more dramatically while Frisk kept up the best he could without messing up his performance. The two danced in a sort of rhythmic orbit that only grew livelier as the song approached its climax.
Meanwhile, Sans sat on the other end of the phone in silence and let the memories wash over him.
Frisk's performance was so vibrant and energetic that Undyne turned around to watch and Toriel started humming along.
When the piece was reaching the end, Frisk went back to walking. Papyrus caught on and slowed his pace, too.
Then, Frisk said, "When the sun rose the next morning, the dancing stopped and the musicians put away their instruments. The spirits of the dead returned to the other side and the merrymakers returned home to rest after their long night of revelry. Their energy was spent. Their dead loved ones were satisfied. Everyone would go home happy despite having spent all night doing the dance of the macabre."
Frisk ended the piece and let his arms rest by his side.
Everyone started clapping while Undyne said, "I'm impressed, punk. Great job! It looks like your determination is stronger than you thought."
Frisk smiled and breathed deeply as his HP rose another point. Meanwhile, back in the Ruins, Sans smiled to himself as his HP rose by another point, too.