Web fiction has its own vocabulary, and most of it describes how power works in a story rather than where the story is set. The essential terms fall into a few groups: the genre labels (progression fantasy, LitRPG, cultivation, system apocalypse, isekai, dungeon core), the mechanics vocabulary (the System, stat block, leveling, class, mana), the cast shorthand (MC, NPC, ROB), the reader slang you meet in reviews ("crunchy," "OP," "power fantasy"), and the publishing words for how a serial is actually released. This glossary defines the ones you will actually meet, with the books that anchor them.
If you have wandered into a Royal Road comment section or a progression fantasy forum and felt like everyone was speaking a slightly encrypted dialect of English, you are not wrong, and this page is meant to decrypt it. Running a web fiction platform, the thing I notice most is that the vocabulary is not decoration; it is how the community sorts, recommends, and argues about books, and a writer who uses the terms correctly signals that they actually read in the genre they are writing for. I have grouped the words the way readers actually use them rather than alphabetically, because "crunchy" and "OP" belong to a different conversation than "backlog" and "Rising Stars," and understanding which conversation a term comes from is half of understanding what it means.
The genre labels, from broadest to most specific
The genre labels in web fiction are reader-facing tags that sort stories by how the protagonist gets stronger, not by where the story takes place. The broadest useful term is web fiction itself, meaning stories published online for direct reading, and its close relative the web serial, meaning fiction released in installments one chapter at a time while it is still being written. Underneath that sits progression fantasy, the load-bearing category of the modern scene, which covers any story built around a character growing measurably and visibly stronger over a long arc, whether that strength is magic, martial skill, or something stranger. Will Wight's Cradle is the canonical example of progression fantasy that carries no game numbers at all. LitRPG, short for "literary role-playing game," is the subset of progression fantasy where the growth is shown through explicit game mechanics, the levels and stat sheets and skill notifications printed right on the page, as in Defiance of the Fall. If you want the full anatomy of that one, I wrote a separate piece on what LitRPG actually is, and the whole family tree lives in the web fiction genres guide.
The rest of the labels are variations on that spine. GameLit is the umbrella under which LitRPG sits, covering stories with game elements that do not necessarily surface as numbers. Cultivation fiction, rooted in the Chinese xianxia and wuxia traditions and brought to English readers largely through translation sites like Wuxiaworld (founded in 2014), follows characters who ascend through ranked realms of power by refining body and spirit, usually at a real cost. A system apocalypse is the flavor where reality is suddenly gamified by an arriving System, turning the modern world into a leveling ground, which is the engine of Matt Dinniman's Dungeon Crawler Carl. Isekai (Japanese for "another world") means a protagonist transported into a new world, often a game-like one; the near-synonym portal fantasy is the older Western term for the same move. A dungeon core story inverts the usual view and puts the reader inside a dungeon that builds and defends itself, and kingdom-building fiction hands the protagonist a territory to govern rather than only a sword to swing. You will also see harem used as a content tag, meaning the protagonist has multiple romantic interests at once, which tells a browsing reader what to expect more than it describes any craft.
The progression vocabulary
The progression vocabulary is the set of game-derived words that describe the actual machinery of getting stronger. At the center is the System, usually capitalized, an in-world rules engine that assigns levels, classes, and skills and often narrates its own decisions through pop-up notifications. Its most visible artifact is the stat block, the boxed panel of attributes (strength, agility, intelligence, and their cousins) that interrupts the prose to show you exactly where the character stands. A level is a discrete step of power, leveling is the act of climbing those steps, and a class is the role or archetype (mage, warrior, necromancer) that shapes what a character can become. A skill is a specific learned ability, and mana is the magical fuel most systems spend to use one, with qi playing the same role in cultivation settings.
The words for balance and exploitation come from tabletop and video gaming almost unchanged. Power scaling is the ongoing question of how strong a character is relative to threats and to their own past self, and getting it wrong is the single most common structural failure I see in submissions. A build is the particular combination of stats, skills, and class choices a character commits to, and min-maxing (sometimes called playing a munchkin) is the practice of optimizing that build ruthlessly for power at the expense of everything else. OP, short for overpowered, describes a character so strong that tension leaks out of the story, which readers use as both praise and complaint depending on whether the book earned it. And deus ex machina, the old Latin term for a rescue that arrives from nowhere, is the accusation readers reach for when a power-up appears exactly when needed without any setup, a charge that lands especially hard in a genre whose whole promise is that growth should feel earned.
Who's who in the cast
A handful of abbreviations do most of the work when readers talk about characters. MC means main character, the protagonist the whole progression arc hangs on, and NPC, borrowed straight from games, means anyone in the cast who is not the MC, sometimes with a faint implication that the character is thin or purely functional. ROB stands for "random omnipotent being," the near-godlike entity that reincarnates or empowers the hero at the start of many isekai stories, a term that started in fan fiction and migrated into original web fiction wholesale. Love interest is self-explanatory, and waifu (from the anime fandom) is the affectionate reader shorthand for a favorite female character, romantic or otherwise. The party, another gaming import, is the core adventuring group the MC travels and fights alongside, and how well an author writes party banter is often the difference between a serial readers binge and one they drop. My feeling is that the cast shorthand is where newcomers give themselves away fastest, because using "MC" and "party" naturally reads as fluency while overusing them reads as costume.
The slang you'll see in reviews
Reader slang is where web fiction's culture shows, and a review's word choice usually tells you more about a book than its star rating. "Crunchy" describes a story dense with visible mechanics, all detailed stat blocks and damage numbers and skill trees you can follow like a manual, the opposite of a light or narrative-first read where the math stays offscreen. "Power fantasy" and "wish fulfillment" both name the pleasure of watching a protagonist accumulate strength, status, and competence; readers use them neutrally as often as critically, because delivering that pleasure well is a genuine craft and not a flaw. "Filler" means chapters that pad the wordcount without advancing plot or progression, and "copium" (a joke blend of cope and opium) is the fandom's word for the strained optimism readers deploy when a favorite story starts slipping. You will also hear about "the slog," the mid-book stretch where momentum sags, which I have written about at more length as the mid-novel slump. I think the most useful thing to understand about all this slang is that it is affectionate more than it is harsh; a genre that calls its own comfort reads "trashy but fun" is not being cruel, it is being honest about why it shows up.
The publishing words
The last cluster is about how web fiction is released, chapter by chapter, rather than about the stories themselves. A chapter is the unit of release, an arc is a multi-chapter story movement (roughly a season), and a book or volume collects several arcs into a bindable whole. A cliffhanger is the unresolved beat that ends a chapter to pull readers into the next one, and a backlog is the buffer of finished-but-unpublished chapters an author keeps ahead of the release schedule, the single best defense against a hiatus, the dreaded pause when a serial stops updating. Advance chapters are the ones readers pay to read early, which is where most web fiction money is actually made; on IlorisNovel that early access runs through a coin paywall where the author keeps 93% and cashes out directly, and you can feel out the whole flow in the no-account editor demo. Rising Stars is Royal Road's discovery list, the closest thing the genre has to a bestseller chart and the make-or-break moment for a new serial's traffic. Cross-posting is publishing the same serial on more than one platform at once, and a rewrite is the fraught decision to go back and redo early chapters, which readers greet with a mix of hope and dread.
None of these definitions are laws, and half of them are contested somewhere by someone with a good argument, which is exactly what you would expect from a living genre still inventing itself in public. The vocabulary matters less because it is precise than because it is shared: it is the handshake that tells a reader you belong to the same conversation they do, and it is the fastest way for a new author to signal that they wrote their book from inside the genre rather than at it. Learn the words, use them the way readers use them, and the community stops sounding encrypted and starts sounding like home.
by Jacob Tam · August 7, 2026
I run IlorisNovel. If you want to see what writing here feels like, you can try the editor with no account.