Given the fact that the wiki will seemingly orient itself around games in general, not just gacha games, a slight rewrite of the start might be necessary.
This is a guide on how to tag characters and their alternate outfits that appear in video games which have obtainable named outfits, specifically gacha-styled mobile games and computer games which have such functions.
Throughout recent years, there lacked a means of standardizing how alternate costumes for characters in games should be tagged on Danbooru, mainly those in gacha-styled games. The conventions that work for one title may not work so well for another, which then leads to inconsistencies and confusion, and other titles may have just ignored them entirely. The aim is to define why there is a difference between video game media and other forms of media when it comes to handling characters and named outfits, and then use already-existing tagging conventions and examples to clarify things. This process can then be standardized so that what works for one game can work for another, rather than users making up unique rules on a game-to-game basis that will wind up conflicting with each other.
Though most games do have fairly standard/consistent systems in place, discussion surrounding Fate/Grand Order has necessitated its distinction into its own separate discussion due to the unique circumstances surrounding how it releases characters and alternate outfits. This article, though it may reference that game, has minimized examples originating from it because of that. For specifically discussing tagging conventions for F/GO, please go to topic #17356 ("The Fate/Grand Retagging Project").
TERMINOLOGY
Gacha (ガチャ) is shorthand for gachapon (ガチャポン), which in itself is an alternate saying of gashapon (ガシャポン). Whatever the reading, this is a type of Japanese-produced vending machine that customers dispense money into, then they twist a crank and the machine dispenses a plastic egg containing a randomly-selected toy or prize. Usually this is one toy out of a collectible set, incentivizing customers to pay more to complete the collection. Gasha/gacha is the Japanese onomatopoeia for the sound of the crank being twisted, while pon is the sound of the toy dropping into the receptacle.
Similarly, a gacha video game is a branch of mobile gaming where players save up a fictional in-game currency, then use it to roll the virtual vending machine (think of spinning a slot machine or roulette wheel). What players roll for tend to be desired characters, character classes, weapons, vehicles, materials, add-ons or whatnot, depending on what the game offers. Additionally, non-gacha video games can have elements or systems which resemble gacha mechanics, whether it be monetized MMO-style loot boxes, social-network gaming microtransactions or modern PC-gaming loot crates (as developed from the FIFA series of games from 2008 onward, and popularized by Team Fortress 2 in 2010). These games may also have the option to directly purchase the given desired item. The majority of this discussion is going to cover characters and named outfits, since Danbooru is a character-based imageboard.
DANBOORU’S TAGGING GUIDELINES
Danbooru’s guidelines for separating everything with tags work somewhat differently for video games with gacha elements, due to the complex nature of gacha-styled mobile games, and how these kinds of games in general release characters, alternate costumes, and/or alternate forms. Though the article focuses largely on gacha-styled mobile games, due to the bulk of new releases originating from there, the guidelines and categories set aren't exclusive to them, as the conventions aren't either.
The crux of this article comes from when an already-released character is recycled and given a different costume. This then complicates tagging these alternate costumes because of a variety of reasons. While they may literally be the same character just wearing a different outfit, the game itself may treats them as an entirely different character by giving that costume an official name. Compounding things is that these characters may sometimes possess different skill sets, character classes, backstories and may even be categorized according to an in-game ID number, in such a case further proving that the developers intended for these alternate costumes to be treated as full characters, and not merely as skins (examples of these especially being found in Honkai Impact 3rd and Fate/Grand Order).
That last sentence is especially important for Danbooru’s purposes, particularly the phrase, "alternate costumes to be treated as full characters". When it comes to video games, that is how a named outfit should be treated here – with a character tag, not just treating it as the same character wearing a different outfit. For Danbooru’s purposes, this is called a variant. Other terms that can be used interchangeably are forms, versions, and alternate costumes, but this article will stick to the term variant for consistency's sake.
This has been a growing source of confusion in the last few years for one reason: Most forms of media don't name their alternate outfits. For a non-video game example, Yoko Littner's swimsuit (post #178763) that she wears in a single episode of Tengen Toppa Gurren Lagann doesn't have an official name attached to it; it's just a swimsuit. Another example is Tomoe Hotaru's black dress (post #2227732) that she frequently wears in Bishoujo Senshi Sailor Moon. The creators never assigned a name to it; it's just a dress she wears. Therefore, regardless if the costume comes from an anime, video game, movie, book, or other form of media, if the creators/developers don't give a name to an alternate outfit, then don't give it one here.
Some copyrights on Danbooru, notably Pokemon (anime), do sometimes tag individual sources if the art in question is based on it, such as Pokemon Sun and Moon episode #68, where the leads of the show end up wearing nurse outfits, and art ensuing from it. But in such an instance, the outfit itself still isn't tagged, but rather the episode itself is as to provide a convenient means of searching for that art.
Further discussion is needed regarding an outfit that was initially released without a name, then retroactively given a name later in the franchise's life, and whether or not it should be likewise retroactively tagged with a new character tag. While this is uncommon, it does happen.
- Benit149
In contrast, a gacha example would be Azur Lane's Sirius, who has a swimsuit that is officially named Midsummer Seirios. This means that it should be given the same treatment here by denoting a character tag (or chartag) to it.
That is the primary difference between tagging characters and outfits from gacha games and those from non-gacha titles. Official sources will name a character's alternate outfit, and Danbooru users then tag according to whatever conventions the official sources use. Akin to the example provided earlier with Pokemon, this is done for more convenient searching, as the end user can either specifically search for the given outfit, or filter it out from the search.
Some of my wording may be repetitious, but I think it's a good start.