Undertale: The Machine
Unknown Echo

Asriel, in the Royal Guard's barracks in the city of New Home, addresses his employees as his sibling Chara walks up behind him. Asriel, with his white fur poking out of his robes, now also dons a few metal pieces of equipment, fixated along his limbs and chest. He looks like a true royal captain.

"Chara?" Asriel asks. Asriel motions to his men, and the rest of the soldiers salute and march away.
"So, what do the royal guard even do if there's no war?" Chara asks. Asriel crosses his arms.
"Well for one, we still keep a stern vigil within the Ruins. Never know when a human is going to fall, even in this new, better world. We need trained professionals to apply aid to the kind ones, and provide info to us about ones that might have other ideas." Asriel explains cooly.

"Other ideas, huh?" Chara says. Asriel notices that his sibling is also wearing armor, shoulder pads and a leather vest, the shoulder pads splay a cloak that protects them.

"What's with the getup?"
"I've decided to join the Royal Guard myself." Chara explains with a grin. Asriel looks Chara in the eyes and frowns.

"This isn't a game you know. This is a job, a career, a way of life. You'll get bored of it." Asriel explains, his royal demeanor really kicking in since he became a teenager.

"I want to protect our home too, and if a human with foul intentions does fall, monsters are too weak by themselves. You should know that more than anyone."
"…" Asriel goes silent.
"Let me do this."
"It will require conviction and tenacity. Long hours doing potentially nothing, with the possibility of a battle to the death."
"Don't talk to me like I'm some FNG, we've both been through worse."
"…" Asriel smiles and shrugs.
"Fine. Welcome aboard. Go see dad. He'll get you drawn up."
"Sure, Asriel-" Chara says, beginning to walk away.
"No…?" Chara says, turning around.
"That's SIR, private."
"…" Chara grins and gives a mock salute, sticking their tongue out.
"D-Dismissed. Out of my sight you child!" Asriel coughs with a blush.
"Hehehe…" Chara laughs as they vanish from sight.

"Can you believe how much our son has grown, Asgore?" Toriel asks her nearby husband, king Asgore. They both smile, looking down from their loft to the city below, seeing Asriel in the barracks.

"He has taken to leadership quite well. He and Chara have become fine adults."
"Yes, and they treat this other human, Frisk… as if he were a longtime friend. To be honest, I feel that way too."
"Indeed. He just has that aura about him, a child of immense Determination. I was glad that he gets along so well with Chara and Asriel. Sometimes when we talk, it seems like he knows things about me that I don't even know about myself." Asgore muses. Toriel looks over, surprised.

"I… feel the exact same way. Frisk is a very unique young man, though I am certain we've never met, it appears like he and I are longtime friends." Toriel says with a smile.

Asriel sits down on a seat, looking at the barracks in the city of New Home, before noticing someone here. Someone he hasn't seen in a few weeks.

"Hmm? Royal scientist Gaster, what brings you here?" Asriel asks. Gaster bows.
"Hello, your highness. I just came to… check on things. Do you know where Frisk is?" Gaster asks. Asriel puts a finger to his chin.
"He said he wanted to explore some hidden grottos in Waterfall. Why, is something wrong?"
"There might very well be, your highness, but I can't be sure. I will have to claim verification." Gaster says with nervous eyes, his labcoat blowing in the breeze of New Home.

"Sounds serious. I can send a scout to look for him, though I ask you to tell me what you found."
"Very well. It's probably nothing… but we appear to have slipped into… a twenty-seventh rotation."
"Rotation…? Oh, you mean those things that you and Frisk were doing while I was… well, dead."
"Right… but we left on twenty-six, this being the last Rotation. But… my machine is registering an additional reset."
"But that can't be right, Frisk said he doesn't have control of the timeline anymore…" Asriel says, worried. He meets eyes with Gaster and they both come to the same conclusion.

Someone must be controlling the timeline, someone other than Frisk, Asriel, or Chara…