AdditionalTale

Description
AdditonalTale was an AU of UnderTale, this universe was the home of Containment!Sans, as well as the last AU created

AdditionalTale was an attempt by Bladeinthelight to replace Undertale as the core of the multiverse, so that he could begin to repair the multiverse based off of it

Story
Frisk had multiple times passed through the underground, never had they once harmed a monster. They continued several times before being confronted by their uncle Sans, who informed them about his knowledge of the forever repeating events. Frisk was overjoyed at the idea that they could have someone else keeping track of the events, and so for a time everything went quite well.

The day came when Sans felt something wrong in his soul, and so after Frisk passed him by, he entered the ruins to confront his sister serif about the humans almost frigid behavior, though he only found a silk robe and a pile of dust.

Sans teleported to the core, waiting for them, hoping he could save Papyrus, his brother, and Gaster, his father, as they were visiting the Core. He waited for what seemed like hours, until the human came along, and Sans tackled them, shoving both of them into the core.

Frisk's human body burned up in the heat, though Sans survived, waking up within the Anti-void, he found that during the fall the human had stabbed them in the eye, and he began exploring, trying to find help

Characters
Sans a royal scientist, one of the scientists who designed the core, and the Sans who would take on the identity of Containment!Sans

Serif Sans's sister and care taker of the ruins, as well as Frisk's adopted mother

W.D. Gaster Head royal scientist and father of Sans, Papyrus, and Serif.

Papyrus second in command of the royal guard, brother to Sans and Serif

Alphys royal scientist and Sans' current girlfriend.

Trivia

 * AdditionalTale is currently still fully intact, having never been fully destroyed by Frisk
 * The Au is shrouded within code that makes normal travel back and fourth impossible, and such Alphys is currently trying to develop safe travel in and out so that she can find Sans