Echo

In Megalophonic, it takes place in the Underground, 5 years after the neutral timeline. It’s been 5 years since Frisk disappeared with the other 6 human souls. Toriel is the Queen again after Asgore’s death. Two souls have been taken into possession in the last five years: A Magenta Soul and a Green Soul. (Perseverance and Kindness) (Edit: Frisk would still be a child, being less than 16 years of age.)

Sans was appointed the royal scientist with Alphys as his assistant after the human disappeared with what hope they had left for breaking through the barrier. Sans had found Alphys in the lab, barely clinging to life. After healing her, he made sure that she got the help and therapy that she needed. Soon after, she and Undyne had started dating. Undyne had been the one to help her with her therapy. Sans was promoted to Royal scientist by Queen Toriel after seeing the stress it put on Alphys. Sans took on the new job with ease. After seeing everyone's hopes slowly die, he wanted to help everyone in any way he could.

Alphys & Undyne moved into the ruins after Queen Toriel moved into New Home. Alphys, with her past work experience, was able to set up motion sensors and heat sensors that trigger an alarm when a human was near the Ruins. Two years after Frisk disappeared, a Green Souled human came to the underground. Alphys reported to Sans as soon as the alarm went off. She tried to greet the fallen human, but Sans managed to beat her to them somehow.

Queen Toriel at first wanted to protect the human, resulting in the rest of the Underground revolting in disagreement. Sans spoke with Queen Toriel and she regretfully agreed. She wanted what was best for her people. She didn’t want to, but she needed to kill the human. Sans stepped in, and assured her that he would take over the painless execution of humans, using lethal injections. He ended the human’s life, and secured their soul. A year later, a magenta souled human fell.

Papyrus wasn’t granted Captain of the Royal Guard, but was definitely in the Royal Guard, thanks to Sans’s request to Queen Toriel. He works directly under Undyne as 2nd in Command. He got actual metal armor and was trained to summon his own magical spear by Undyne.

Sans is known as Dr. Slack, and Papyrus is known as Sergeant. Papyrus actually gave Sans the nickname when he went to visit him, and Sans was slacking off in the lab.

(CW: Additional near-death experience for a character after falling from a deadly height, mention of needles/syringe.)

Libby, my OC, was originally human when she fell into the Underground. Dr. Slack went to greet the human, as usual, but something went completely wrong. He came to the usual spot where a human would land on a soft bed of flowers, but her crumpled body was lying on solid ground. The bed of flowers was gone. He became horrified that he didn’t see the human’s soul at all floating above her body. He knew she must still be alive. He rushed over to the human’s body, and she was weakly reaching for anything to relieve her from the pain. He questioned how she was still alive. Then he found it; the human had a fractured Determined soul.

He didn’t know why, but he felt compelled to help the human. Maybe they won’t do what Frisk did. Maybe this human won’t leave. He had to save her. He took a shortcut back to the Lab, carrying her broken body into the med bay. He quickly connected her to the various machines in the room. Her vital signs were pitiful; he honestly questioned if he was connecting a corpse to his machines.

Through rushed experiments and research, he had attempted to infuse the human with the Magenta soul. He didn’t have time to try to inject her with the soul using a syringe or needle. He brought his left hand forward with the Magenta soul in hand, and used his magic to try to force the soul into the human’s Red soul. Nothing was happening. He used more magic. A wave of Deja vu swept over him as he felt immense pain in his left hand. Then, all of the machines connected to the human began to blare and sound off alarms. Sparks started to pop around Dr. Slack. Then, immediate silence. The silence was deafening. There wasn’t even the tell-tale sign of her vital signs ceasing. Just. Silence.

He briefly checked over his machines for any signs of life. He looked around her limp body for any signs of her Determined soul or the Perseverance soul. Nothing.

Libby doesn’t remember much from her past life. She just feels a small twinge of pain in her soul when she tries to remember.

Sans: When in the lab, Dr. Slack wears a white lab coat with the sleeves neatly rolled up, showing his blue gloves. Underneath, he has a black button up shirt and a blue tie with black dress pants. Instead of slippers, he wears blue sneakers. Alphys wears a slightly shorter lab coat, with black pants. He used to wear his gloves on and off, but now wears them 90% of the time in his lab to cover the hole in his right hand, as a result of saving Libby's life. When at home, Sans wears a blue pull over hoodie that has black sleeves and white strings, with black shorts with black and white lines going down the sides. And his signature pink fuzzy slippers.

Papyrus: When patrolling, Sergeant wears a similar outfit to what he wears in UT, but its composed of real metal and he has an orange and silver spear. He has red and metallic silver boots. He prefers to keep his long red scarf worn. When in combat, he wears a spangenhelm-style helmet. When at home, he is usually in comfortable clothes like a T-shirt and relaxed black pants and orange slippers.

Libby: She was originally a human before she fell into the Underground, so she’s still not accustomed to her new skeletal body. She has the usual body of a skeleton, and has dark pink eye lights. When she wants to, she could summon her dark pink ecto hair. It looks similar to a medium-high undercut that’s pulled back into a ponytail. She also has a 2-3 inch long cut that originates from her left eye socket, going down her left cheekbone. She wears slightly baggy clothes due to her insecurity of her new body. She usually wears a black, white, gray, dark pink and light pink hoodie that has a slanted horizontal pattern. She wears slightly baggy capri pants, just barely going past her knees, with a dark pink line going down the outside of the legs. She wears black and white converse-style shoes with dark pink laces.