Rarepair New Year 2026

Why AO3 Tagging

The Official Rarepair New Year Event Raffle began by using AO3 Tags as its metric to codify and define Rarepairs. Even though this year those policies have been relaxed, the Event still requires all rarepairs to be Tagged on fanfic submissions with a standardized Ship Tag.

To make understanding this process easier and more intuitive, this page was written to give you a primer (or a reminder) on how AO3 Tags work in the context of Alternate Universe shipping, and put that into context for the Event's purposes.

This primer will help you figure out how you need to format your Ship Tag on AO3. It pairs best with the basic rundown found in the standard AO3 Tagging primer.

Disclaimer (1): These tagging guidelines and practices are comprised of research and observations from a front-end user of AO3. This Event is not affiliated with AO3, and no AO3 Staff are representative in the hosting, curating, or development of the Event or its guidelines. These guidelines are explicitly written by a user, for other users, for the explicit purpose of users participating in a Fandom Event, and are not to be associated with AO3 as an entity.

Disclaimer (2): Because the Event once relied so heavily on the Canonical status of a Tag, the rest of this page will be using language that heavily encourages using only Canonical Tags, or tags which follow the syntax of Canonical Tags as of the time of this writing. This is the Event's priority for the ease and convenience of the Coordination and Moderation of the Event.

The Event heavily encourages adhering to these tagging practices for the duration of the Official Rarepair New Year Event Raffle, but by no means does it posit that these practices are compulsory outside the Event.

AO3 Additional Tags (a.k.a. Freeform Tags)

The Additional Tags Entry Field is where Freeform Tags go. Freeform Tags are tags which cover any and all Tags which are not covered by the other types of tags. This includes (but isn't necessarily limited to): genre tags, kink tags, squick tags, trigger warnings, categorical tags, event and context tags, and AU tags.

AU Ship Tags

As has been alluded to in previous sections, The Character and Relationship Tags will Synn any AU disambiguating tags that are entered into them, synning them under their Canon-Compliant variations.

This means that, if you want to search for "Underfell Sans/Reader" fics, and you do so using a search in the Relationships Tags, you will end up getting results for all Sans/Reader fics. This makes finding AU content you want seemingly impossible.

The solution is to use Additional Tags.

UTMV AU Tags are already canonized as Additional Tags, both as Character Disambiguating Tags and as Relationship Disambiguating Tags.

This features allows the Event to calculate metrics for UTMV Ships and determine which of them are Rarepairs.

How to Tag a Whole Alternate Universe

When a fic takes place in a specific kind of Alternate Universe, or involves multiple characters from the same Alternate Universe, you may find you want to add an AU Tag in the Additional Tags entry field using the Full and Proper Name of the AU in question with the pre-established AU format.

Examples:
Alternate Universe - [AU Name] (Fandom)
Alternate Universe - Underfell (Undertale)
Alternate Universe - Dancetale (Undertale)

This is used to broadly search/filter the AU itself. Other, broader kinds of alternate universes (such as Victorian Era, Vampires, and 1920s) are also used with this syntax, sans (heh) the Fandom tag, but for the purposes of this Event, those Broader categories won't be factored in to determine Rarepairs. The event will only recognize Fandom-Specific AUs, which are disambiguated with a Fandom designator (as used in the Undertale/UTMV fandom) or which have a Fandom-Specific Term in the name of the AU itself (making the need for a fandom designator redundant in that particular fandom).

Tagging the AU itself is not required for a work to be a valid entry, but knowing and understanding what the "Full and Proper Name of the AU" is for the next sections to make sense.

The Event will recognized any AU tag which has been canonized and wrangled already. In the event of any disputes over naming conventions, the Event will defer first to pre-established AO3 tags, and second to any primary sources which can be found from the original creator of the respective AU(s).

Additional Tags: Character Disambiguating Tags

If an AU Character is involved, it is recommended to add a Character-Disambiguating Freeform Tag in the Additional Tags Entry Field. A Character-Disambiguating Freeform Tag is a Freeform Tag that specifies a distinction for a particular AU variation (or a distinct and named Original Character) in place of a true Character Tag.

AU Character Disambiguating Freeform Tags are considered by the Event to be child-tags of the Canonical Character True Character Tag. To qualify for Bonus Tickets, a Work must tag the parent Character Tag along with the Character-Disambiguating Freeform Tag.

The syntax for an AU Character-Disambiguating Freeform Tag is:

[AU Name] [Source Material Name] (Fandom)
Examples:
Underswap Sans (Undertale)
Underlust Papyrus (Undertale)
Reapertale Toriel (Undertale)

There are unusual circumstances that break from this format, especially when the character in question is known by a Nickname. In cases like this, a Pipe (|) may be used to separate and express the two identifying names.

Examples:
Xtale Sans | Cross (Undertale)
_____tale Sans | Ink (Undertale)

The format may also be broken by inserting a disambiguating (fandom-specific) modifier between the AU Name and the Source Material Name:

[AU Name] [Modifier] [Source Material Name] (Fandom)
Examples:
Dreamtale Nightmare Sans (Undertale)
Aftertale Classic Sans (Undertale)
Aftertale Geno Sans (Undertale)

You may also find further extensions with prefix modifiers, like "Child" or "Bara" or "Evil" or "Abusive" or "Alpha", but for the purposes of this Event, these broad, secular (non-fandom-specific) nuances probably won't affect the rarepair determination.

To put this another way, as an example: Bara Underfell Sans (Undertale) is probably not distinct enough from Underfell Sans (Undertale) to convince the committee.

Multiverse Disambiguation Policy

In the same vein, MAUs (such as but not limited to: Underverse) are also not considered as distinctively relevant, as the characters which comprise them do not have any disambiguating features to make them different from their non-MAU counterparts for the purposes of shipping.

To put it another way: it would not make sense to disambiguate "Underverse Underfell Sans" from "Underfell Sans", or "Leviathantale Reapertale Sans" from "Reapertale Sans", in such a way as to make the ships they are a part of unique to each other, and therefore they will be synonymous for the purposes of this Event.

Rarepairs WITHIN those continuities are still eligible (such as if Underverse Red/Lust is the focus, or Leviathantale Papyrus/Nightmare), but the continuities themselves do not inform upon that judgment. (Underverse Classic/Red isn't distinctive from Non-Underverse Classic/Red to make it relevant as a taggable rarepair).

Obscure AUs & Original Characters Policy

Personal and Less Well Known AUs are perfectly valid, so long as they feature 3 or more Canon Character derivatives. AU types which do not feature at least 3 will be considered OCs for the purposes of this Event, whether or not their correct and proper tagging would designate them as such.

Example: While Ink is to be tagged by his name using his Character-Disambiguating Freeform Tag, he is for the purposes of this Event designated as an OC.

As OCs, they will be categorized for the Purposes of this Event as being a Child-Tag of the "Original Character" tag, and by extension ships involving them will be considered Child-Tags of "[character]/Original Character" Tag.

This year, OCs will be considered on a case-by-case basis. However, any OC which already has a Canonical Character-Disambiguating Freeform Tag will automatically qualify. Pioneering an OC's Character Disambiguating Freeform Tag is outside the scope of the Event's intended purpose, but we're being kinda lax this year.

Additional Tags: Relationship Disambiguating Tags

For ships which involve AU-Characters (or OCs), there must be a Relationship-Disambiguating Freeform Tag in the Additional Tags Entry Field. A Relationship-Disambiguating Freeform Tag is a Freeform tag that specifies a distinction for a (Relation)Ship between one or more particular AU variations (or distinct and named Original Characters) in place of a true Relationship Tag.

A Relationship-Disambiguating Freeform tag is largely ordered the same as a true Relationship Tag: alphabetized by Last-Name, then First-Name. If at least one party in a ship is meant to be the standard, Source Material Character, then the Source Material character(s) will always be listed first, in alphabetical order. Any AU Character will then follow alphabetically:

  • 1st by AU Modifier
  • 2nd by any additional Modifiers
  • 3rd by Canonical Last Name / Family Name
  • 4th by Canonical First Name / Given Name

A Relationship-Disambiguating Freeform Tag has the following syntax:

(Canonical) Source Material Name(s)/[AU] Source Material Name(s) (Fandom)
Example(s):
Sans/Underfell Papyrus/Underfell Sans (Undertale)
Sans/Underfell Sans/Underswap Sans (Undertale)

Ships of course can also be between just AU variants and/or OCs:

Example:
Dancetale Sans/Underfell Sans/Underlust Sans (Undertale)
Underfell Sans/Underlust Sans (Undertale)

Names which include a Pipe (|) are to be alphabetized first by what is in front of the Pipe.

Examples:
Dreamtale Nightmare Sans/XTale Sans | Cross (Undertale)
Killer Sans/XTale Sans | Cross (Undertale)

Due to the character limit, larger poly ships may need to use shorthands. Use best judgment for when to omit what modifiers. Avoid using Ship-Names except as a last resort for large polycules which exceed the tag character limit. When using shipnames, remember to include a fandom modifier for clarity:

Example:
Polyamorous Bad Sanses | Nightmare's Gang (Undertale)