* Is this name correct?

* CORETale has not been given an official name; as such, this name is purely conjectural. However, it will be used until an official name is released.

CORETale, or CORE!Frisk AU, is an AU created by Tumblr user DokuDoki exploring the titular character CORE!Frisk and their actions. This AU was the first to coin the term "multiverse" in the fandom and one of the first to promote the multiverse theory, and has significantly contributed to the growth in popularity of the alternative universe creation among the fans.

The concept was closely based on the very popular theory that W. D. Gaster has at some point fell into his creation (the CORE) and became scattered across time and space. In this AU it is assumed that a human falling into the CORE is affected in different ways than a monster would be.[1]

The AU follows its central character Frisk who upon falling into the CORE has attempted to RESET on the brink of being scattered across time and space, which caused them to not only be scattered in their own timeline, but in every timeline. Frisk has gained the ability to be everywhere at once and appear anywhere they want, at cost of losing their RESET powers and humanity.

Frisk's adventure in the Underground is largely identical with the events in the game, specifically the Pacifist Run. Mesmerized by the adventure, they began to continuously RESET the happy ending just to re-experience everything all over again, not realizing their actions are wrong and harmful to the others - especially Sans, who was aware of the loop they were all trapped in. This took a great toll on his mental health. One day as he witnessed Frisk outside of the broken barrier about to RESET the world he snapped, dragged them all the way to the CORE, and threw them inside in hopes that erasing the human from the existence will at last free him from the circle. As the terrified Frisk attempted to save themselves through resetting, their SOUL was directly exposed to the CORE's magical radiation - combined with this and the fact the RESET and the SOUL scattering aligned perfectly, the event has caused them to become omnipresent.[2]

Currently, the story of the AU hasn't further explored what has happened in Frisk's original timeline after the incident. However, it is known that no one remembers the existence of the human and that the Barrier is often believed to have disappeared on its own or destroyed by an angel.[3]

CORE!Frisk also is a mayor character in FMSDraws' Ask Poppy askblog, and while not made by Dokudoki themselves, is canon to CORE Frisk.[4] In this askblog they adopted a girl named Poppy living in the Omega Timeline. They're referred to by her as "Granpa", by the logic that old people have grey hair, and since theirs is grey, they're a grandpa.


CORE Frisk


CORE!Frisk is a fickle, enigmatic child who is unable to mentally grow despite their nigh infinite knowledge and wisdom. They appear to have strong personal philosophies about the good and the bad that on the surface don't always seem to make sense - as they are able to befriend the antagonistic Reaper!Chara, but despise the equally antagonistic Reverse Reaper!Frisk. According to the author, CORE!Frisk falls into the moral alignment of a Chaotic Good.

To Frisk, lives of the individuals is what matters above the grand schemes of the multiverse. In fact, CORE is of the opinion that the intangible concepts and rules - such as the universal balance - are entirely man-made and following them is harmful to the inhabitants of the timelines. Their belief is so strong they become incredibly condescending towards anyone who values such concepts as a "greater good".

Even though Frisk is incredibly open-minded, somewhere deep down they believe no one understands things better than they do and may subtly treat everyone as such. This behavior tends to amplify the more they dislike someone.

It appears that CORE!Frisk suffers from some form of PTSD, as they are greatly terrified of the sound of sirens, gunshots, planes, and explosive noises such as fireworks. They also get a panic attack and become unable to move properly if they're pointed at with a gun.[5][6]


By becoming scattered across time and space, Frisk has gained ability to be everywhere at once known as omnipresence. This means they are able to observe everything in the existence, even the typically unperceivable things (such as colors invisible to the human eye, the atoms, etc.) in all timelines at once, in all of the presents, the pasts, and the futures.[7] They can physically appear anywhere at anytime they wish, however because of the nature of the timelines and the multiverse their chance of manifesting is always exactly 50%, making their involvement in events rather inconsistent and at times seemingly random. It's been hinted that their appearances are overcrowding the timelines with unnecessary splits where they shouldn't be - whether this has a negative effect on the multiverse as a whole is unknown.

CORE!Frisk's iconic grey appearance with two large black sockets is in fact not "them", as they technically don't have a single body.[8] While it is tangible enough to be able pick up light objects, anything above the weight of "plate with a lot of spaghetti" will phase through the child's form. This makes Frisk practically immune to the physical attacks but some things can still affect the form.[9] Their eye sockets are connected among each body currently manifested, allowing Frisk to use them as a sort of "portal" among the timelines for transporting objects small enough to fit through the socket.

While not possessing any flashy active powers, CORE!Frisk is without doubt one of the most powerful characters in all of Undertale AUs through their sheer knowledge and involvement alone. Because of their omnipresence they are technically a part of every alternative universe ever created, whether they make an actual appearance or not. It is unknown whether Frisk can physically manifest in specialized locations such as The Maker's Punishment, Christmas Party or anti-void, however it's been confirmed Frisk can directly perceive even typically inaccessible places. An important thing to consider is their known involvement with The Omega Timeline, also a specialized location, which would imply CORE!Frisk either simply chooses not to go these places or can only appear if certain conditions are met.


  • "So, go ahead and watch everything from above like some gods, if that's what floats your boat. A person's life might mean nothing to you, but to that person it means a lot. Go ahead and sulk about how you couldn't save them because of fate while I go save them! lol"
  • "Some timelines are truly miserable... And then there are timelines where everyone has Mettaton's legs except Mettaton, or a timeline where I'm an octopus. Seriously, what's the point?!"
  • "Wiggity wack what's up, pumpkins? I have crafted this totally cool outfit just 4U in order to satisfy your curiosity. ... uh... swag."
  • "Your impact is a lot less significant than you think, Sans. You're not special, nor a priority. Definitely not the worst out there."
  • "Oh my? I see where this is going. You're trying to make me flustered, or embarrassed in general. Alternatively you want to see whether I'm capable of keeping a straight face during the explanation. I'm sorry to disappoint you, but I'm afraid that won't work. Not with something like this. I'm used to people trying to make me react through dirty questions. Well, I don't mind explaining to you what tentacle incest is, but what's the point? After all... you already know, don't you?"


Sans is the person who threw Frisk into the CORE in a (successful) attempt to stop the timeline RESETs. While he doesn't directly remember the human, thanks to his special notes he's aware of what happened despite having no recollection of the incident. It appears he still carries resentment towards Frisk and their past actions.


Very little is revealed about CORE!Frisk's Chara so far. It is confirmed that Frisk was unable to see Chara despite the first human being bound to their soul as a ghost.[10]


Omega Timeline


Created by FMSDraws

The Omega Timeline is a timeline that works as a meeting room for all other timelines. No one knows of its existence or how to get there unless they are told by CORE!Frisk.

The Omega Timeline (OT) is a special dimension that connects all Undertale timelines and AUs. It has become a new home for people whose timelines are no longer habitable or have nowhere else to go, as well as a safe place for those who don't have one in their own world. That doesn't mean this timeline is only for people experiencing hardships, however - anyone can be invited if CORE!Frisk chooses to do so.

While the dimension has always existed, it was CORE!Frisk who has claimed its ownership and with the help of many shaped it into the safe haven it is now. The first person other than Frisk themselves has set foot in the OT approximately one thousand years ago. The place was at the time empty safe for the entrance, and it was - quite frankly - depressing and sensory depriving. Joining their forces, people started to bring in items and resources from their old timelines, including the stone to build the paths from and the ground to plant the trees in. Through the decades of hard work, the OT has finally become a place worthy of being called haven. The process is still not complete, and the timeline continues to develop more and more.

To someone new to this place The Omega Timeline might look like an average little town; the most notable difference being the lack of horizon, and especially the blank, featureless sky with occasional blue clouds (the recent achievement made possible by the brilliant minds of the OT who grew sick of the white nothingness above their heads). Perhaps the most jarring cultural shock the newcomers experience is the lack of day-night cycle and proper weather, something yet to be achieved through the magic and science. You should sleep with the curtains closed until we figure it out

However, the sky will inevitably always be blank white without any moon or sun, and thus without the day-night cycle. Recently, the local scientists were able to develop special weather satellite machines hovering high above the ground that create blue clouds able to rain or snow, making a gust of wind every time they fly over above. It was a revolutionary invention to mimic weather and make the blankness less potentially maddening.

(This information has been copied straight from the Omega Timeline's official Discord role-play server)

The timeline was discovered by CORE!Frisk through their omnipresent abilities. Approximately one thousand years ago they brought the first inhabitants to the OT, back then devoid of anything but a single door. (Note: It's currently unknown whether this door was always there, whether Frisk somehow got it in or built it, and whether this door has a specific appearance or changes according to the timeline its last visitor is associated with.) This means that the Omega Timeline was properly inhabited and cultivated for at least one thousand years. It is currently not specified whether the timeline was ever entered before this period, but it's confirmed that the current civilization is the first one to claim the timeline.



CORE Frisk

  • An early concept of CORE!Frisk was much darker and disturbing than their current version - their legs were cut off and bleeding profusely, and they had a large open wound on their stomach. They were also able to levitate and manipulate electronic objects, much like the amalgamate Memoryhead.
  • Their full name is Frisk Marusina, their birthday is February 29th, they're nine years old, and they are four feet tall.
  • According to the author Frisk was born in the country of Slovakia set in a near alternative future where it enters a civil war.
  • Frisk's personal philosophy was inspired by a single quote from a RTS video game titled Original War, in which one of the minor characters said "I know, [my life] might not mean much to you, but to me it means quite a lot."
  • CORE!Frisk has their own in-universe Tumblr blog with username coreo that is described to be "one of the greatest mysteries of the 21st century. [It has] millions of subscribers among which are scientists and historians who keep an eye out for possibly breakthrough updates which will help to advance the humanity."
  • They run a business called CORE!Frisk's Dumb Ask Disposal Service, or short DADS, dedicated to removing the unwanted asks from people's inboxes.[11]
  • They have dysgraphia.[12]
  • Frisk has burn scars on their back.[13][14]
  • In past the author has described CORE!Frisk to be able to absorb souls - a concept which was scrapped completely.

Omega Timeline

  • While most believe the OT to be a place solely for Genocide route survivors, there are many people who are just there to meet other people or volunteer to help those in need.
  • According to the creator, the OT was presented as the iconic white void in its comics only because she was "too lazy to draw a proper background". The white void concept has however become so popular among the fans she eventually just "rolled with it and built everything around it".
  • An early concept described OT as a place which can create its own environment based on the objects people "plant" inside the timeline. This was eventually scrapped and now everything in the OT except the door/s was brought in from other timelines.
  • The OT presented in the comics has a single door serving as the first time entrance for the newcomers, and people can leave and reenter the timeline through any door they wish; however in its official Discord server, every time someone enters the timeline a new door appears out of thin air in a location known as "door area". The person can then only exit the timeline through this door, after which it disappears.
  • Some occupants can get a title of Caretaker. It would appear their job primarily entails helping the new members of the timeline and administration of the local events; whether they're involved in more behind the scenes stuff is unknown.
  • More question answers; Glitch Hop isn't going to destroy the OT. We've gathered an army in case that ever happens
  • You can't access other AUs from the OT; you can only access the timeline you entered from.


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