# Worldtable > A place to build a world in any era (fantasy, present day or science fiction) and > have an AI game master run it. Builders shape > a map, peoples, magic, a cast and rules in the World Studio and invite players; a > language model narrates and voices every character, and a game engine decides what > actually happens. Free to build, plays in a browser. Players type what their character does and the world writes back. The distinction the project cares about most: the model narrates and never resolves. Combat outcomes, damage, travel time, prices, injuries, death, reputation and the map itself are computed by ordinary game code and stored in a database, so they persist between sessions and cannot be talked out of existence. ## How it works - Any era: a world is set in fantasy, the present day or science fiction, and the setting changes the engine as well as the prose. Fantasy: a parchment map, the world's own coins, travel on foot, riding or by ship. Present day: a road atlas map with motorways, railways and airports; dollars; car, bus, train and plane, timed in hours with fares the engine charges; a phone to text and call people between scenes and a news feed; gunfights with ammo, range and cover; dungeons such as subway tunnels and closed hospital wings. Science fiction: a tactical sector map; credits; maglevs, shuttles and jump ships to other planets, moons and stations, each with its own sky, gravity and air. A builder can change any of it and sets how big the world is (one city, a country or a continent), which scales every distance and fare. - Each world's map (coastlines, rivers, biomes, roads, towns) is generated from the land its builder shaped and held by the engine. The narrator can only send players to places on it. - Builders choose up to 20 rules in plain words (whether heroes die for good, the most dangerous thing the world may bring, companion caps, PvP and more); the engine enforces them in code. - Rule systems (Beta, open to every builder): a world can play by a tabletop rule system instead of, or on top of, the native engine. Six come ready-made, each with classes, abilities, conditions, gear, foes and a player handbook: Classic d20 (fifth-edition style, from the SRD 5.1), Forged in the Dark (Blades in the Dark SRD), Moves (PbtA style, Dungeon World SRD), Investigative d100 (powered by BRP), Grim d100, and Duality (Hope and Fear, two d12s). A builder can also compose a system from four answers (seven ways a roll can work: beat a number, roll under a skill, a pool read by its best die, dice plus a stat into bands, counting hits, two named dice where the higher one matters, stats that are dice d6-d12), write rule cards as sentences ("when the Renown clock fills -> 100 xp"), or import a rulebook (PDF, Word, Markdown, text; up to six books read as one) into a system in the book's own words, with anything it had to invent marked as a stand-in. - Dice: when a character tries something risky, the storyteller picks the check in words (which skill, how hard), and code rolls from a seed, grades the result by the world's rules and applies it before the scene is written. Every roll shows in the story as a chip with its full maths; big moments wait for the player to throw 3D dice themselves. - Plugins (Beta): small programs that make a world's own mechanics happen every time (wake at the last shrine you rested at when you die; time lost at a fae revel; a bounty that climbs). Builders ask the Studio's assistant, Hob, in plain words; it writes the plugin, tries it on a test character and explains it. A JavaScript editor and a documented API exist for builders who want the code. - Combat: the model grades a described action for tactics and risk; the engine rolls and applies a damage formula. Outcomes range from CRITICAL to BACKFIRE. Every fight, solo or party, plays out on a battle map with telegraphed enemy attacks; positions and damage are computed before the narration is written. - Multiplayer: worlds are shared, and players can form parties (up to six; each world's builder sets the size or turns them off). A party travels on the leader's march with one clock, fights on one battle map in rounds that resolve at once (everyone declares, every hero acts, then the enemies' announced blows land), splits spoils on a Want/Pass card, and shares one run of a dungeon. - NPCs keep per-character memories and standings (trust, warmth, hostility). - Reputation spreads on a delay measured in in-game days, so news reaches towns you are not in. - Building is free and every account starts with 50 free credits. Each player pays for their own turns (one credit a turn; packs from $5 for 200, or $12 a month for 650). A builder can run a world on their own OpenRouter or OpenAI-compatible key instead, and then players play free. ## Pages - [Landing page](https://worldtable.gg/): what Worldtable is, building a world and playing in one, worlds in any era (fantasy, present day, sci-fi), rule systems and real dice (one roll thrown under five systems), making your own rules, how the engine and the model divide the work, and a live battle map. - [Build a world](https://worldtable.gg/build): the World Studio, for world builders. Shape a map, write peoples, magic, a cast and lore, set rules the engine enforces, and invite your own players, in fantasy, the present day or science fiction. Shown on The Long Ebb, a world built in the Studio. - [Worlds](https://worldtable.gg/worlds): every world its builder has opened to the public, each with its own page at /w/ (premise, lands, peoples, magic, map). - [Fantasy world generator](https://worldtable.gg/fantasy-world-generator): free, no sign-up. One sentence in; a world sketch out (name, premise, founding event, five regions, factions, a villain, three adventure hooks) with a map drawn by the game's own generator in the browser. One per visitor per day; "Keep building it" carries it into the World Studio on the same map. - [Fantasy town generator](https://worldtable.gg/fantasy-town-generator): free, no sign-up. Draws one town or city map (hamlet to capital, eleven building styles, coast, river, hills, walls) with the same generator as the towns in Worldtable worlds. Name every street, district and place; write its lore or have AI write it (a few per visitor per day); download a lettered PNG, Markdown lore, or a town file to reopen. - [Fantasy name generator](https://worldtable.gg/fantasy-name-generator): free names for towns, kingdoms and characters in many naming styles, from the same name engine the World Studio uses. No AI calls. - [Features](https://worldtable.gg/features): one page each on [battle maps](https://worldtable.gg/features/battle-maps), [dungeons](https://worldtable.gg/features/dungeons), [the world editor](https://worldtable.gg/features/world-editor) and [NPCs that remember](https://worldtable.gg/features/npc-memory). - [AI dungeon master](https://worldtable.gg/ai-dungeon-master): what an AI can and can't do as a game master, and how Worldtable splits the job between the model and the engine. - [AI game master for your own setting](https://worldtable.gg/ai-game-master): bring a homebrew world (paste lore, import lore books, books and rulebooks), set rules in plain words or pick a rule system (beta), check the canon, and let the AI run it for players. - [Solo RPG with an AI game master](https://worldtable.gg/solo-ai-rpg): how a solo session goes, memory, playing in short bursts, and rules if you want them. - [AI RPG to play with friends](https://worldtable.gg/ai-rpg-with-friends): delves friends join as guests, parties in shared worlds, fights in rounds, and who pays. - [Modern and cyberpunk AI RPG](https://worldtable.gg/modern-ai-rpg): the seven present-day and sci-fi worlds (a crime city, a zombie town, a city of heroes, space opera, cyberpunk, a wasteland, a city of gates) and what the engine changes: phones, travel with real fares, guns and cover, the news. - [Compare](https://worldtable.gg/compare): how Worldtable differs from [AI Dungeon](https://worldtable.gg/compare/ai-dungeon), [Friends & Fables](https://worldtable.gg/compare/friends-and-fables) and [Voyage](https://worldtable.gg/compare/voyage), including where each of those is the better pick, plus a list of [AI Dungeon alternatives](https://worldtable.gg/compare/ai-dungeon-alternatives), and roundups of [fantasy town generators](https://worldtable.gg/compare/fantasy-town-generators) and [World Anvil alternatives](https://worldtable.gg/compare/world-anvil-alternatives). - [Dispatches](https://worldtable.gg/changelog): the public development feed. Each post has its own page at /changelog/. - [Docs](https://worldtable.gg/docs): how the game works, for players and world builders. What the storyteller decides and what the engine decides; turns, combat, growth, travel, dungeons, parties and playing together, NPC memory; building a world in the World Studio, its rules, and how a builder's own OpenRouter key pays for it. World building is open to any signed-in account (https://worldtable.gg/build). Rule systems have their own pages: [the six systems](https://worldtable.gg/docs/systems), [making your own](https://worldtable.gg/docs/own-system), [rule cards](https://worldtable.gg/docs/rule-cards), [importing a rulebook](https://worldtable.gg/docs/import) and [plugins](https://worldtable.gg/docs/plugins). - [Claude Code and Codex over MCP](https://worldtable.gg/docs/agents): in a private world, each player's own Claude Code or Codex can be the storyteller (and, for owners, the builder) through Worldtable's MCP server at https://worldtable.gg/api/mcp. Worldtable keeps the rules; the agent writes on the player's own plan. ## Notes for automated readers - Every public page is server-rendered; fetching the HTML is enough, no JavaScript execution required. - Routes under /character, /deck, /location, /npc and /burg are per-player and require an account. They are excluded in robots.txt and are not useful to fetch. - Structured data (schema.org Organization, WebSite, VideoGame and FAQPage) is embedded as JSON-LD on the landing page, and BlogPosting on each dispatch. - Questions: the Worldtable Discord (https://discord.gg/vjenDqjpXF).