AI Dungeon

While text adventures have existed since the dawn of computing, AI Dungeon was the first to pair them with a large language model—initially GPT-2, later GPT-3—that could improvise believable scenarios, NPCs, and plot twists in real time. It remains the gold standard for interactive fiction, the genre it helped define. The core mechanic is deceptively simple: you describe an action, the AI narrates what happens next. Repeat across hundreds of turns, and you've collaboratively authored an entire story with branching choices, unexpected consequences, and emergent drama that neither you nor the AI planned in advance. The platform occupies a specific niche: it's not a visual novel with predetermined branching paths, nor is it a roleplay chatbot focused on character interaction. Instead, it's a game engine where you're the player and the AI is the dungeon master. Your input shapes what happens through three distinct modes—Do (actions), Say (dialogue), and Story (direct narration)—giving you granular control over the tone and direction. The genius of the design is that each mode plays to different narrative strengths: Do keeps the gameplay feeling like exploration and consequence; Say makes social encounters snappy and character-driven; Story gives you the power to inject atmosphere or overwrite the AI's trajectory entirely. At the free tier, you're using Griffin, a smaller model trained on the same data but constrained in depth and coherence. Paying unlocks Wyvern and Dragon, progressively richer models that maintain consistent characterization across longer stories and generate more elaborate descriptions. For players transitioning from tabletop RPGs like D&D, AI Dungeon feels immediately familiar—you're rolling for outcomes, interpreting results, and improvising your character's reactions. The difference is that the DM is an AI with infinite patience and no rulebook to slow it down.

Fantasy, Mystery, and Cyberpunk are canonical starting points: each one gives you a scene-setting paragraph and a few lines of framing. Click "Play," and the game thread appears below the scenario. You'll see a chat-like interface with your character's situation at the top and a text box at the bottom labeled "What do you do?" or "What do you say?"—toggle between them using buttons to your left. Type an action: "draw my sword and advance toward the goblin." The AI responds with a paragraph or two of consequence: the goblin snarls, your blade glints, enemies appear from the shadows. You read it, react, and respond again. Do this five or ten times, and you'll feel the rhythm: you push the narrative forward; the AI adds texture, obstacles, and unexpected twists; you react and push again. It's cooperative storytelling at its fastest and most intuitive. Most players' first instinct is to only use the "Do" mode, treating it like a text-based RPG where you input commands. That works, but you'll unlock far richer narratives by mixing in the other modes. Switch to "Say" for dialogue heavy on character voice—"I don't trust this merchant" or a sarcastic quip that the AI will build on. Use "Story" mode when you want to inject pure narrative: "The sun was setting red over the city, and the streets felt dangerous." This direct narration sidesteps the AI's response generation entirely; you're essentially co-authoring, and the AI will pick up from wherever you leave off. Most compelling adventures use all three modes, often within the same scene. If you want to level up beyond the official scenarios, create a custom adventure. Click "My Stuff," then "Create Adventure," and you'll fill in a title, a brief description of the world, an opening narration (a paragraph or two setting the scene), and choose a model. Save it and begin. The AI will take your setup and respond to your first move. You don't need a full rulebook or a detailed world bible at this stage; a 3-5 sentence premise and evocative opening prose are enough to get rolling.

If you're running a 20-turn adventure, you probably won't need them. But if you're building a serialized story, creating a complex world with recurring characters, or running a collaborative session with friends, they become indispensable. Memory is the simplest: it's a sticky note that stays pinned to the AI's context throughout the entire adventure. Write in it the essential facts your character should remember—their name, their goals, what they know about the world. "I am Kess, a smuggler. My sister was killed by the Crimson Syndicate. I'm trying to find their hideout before they kill me too." Every time the AI generates a response, it sees this memory and anchors its output to it. The limitation is token budget: Memory has a ceiling, and once you exceed it, you'll need to trim or migrate long-term worldbuilding to World Info instead. World Info is the power player. It's a keyword-triggered encyclopedia where you define places, characters, factions, historical events, and rules. You create entries with Keys (trigger words like "Starport," "Captain Voss," "Cascade disaster") and Entry (the lore text). When the AI generates text and detects a Key, it automatically injects the corresponding Entry into its context. This lets you build a detailed world that scales. Create a hundred World Info entries about your fantasy realm, and the AI will dynamically pull the right lore at the right moment without you having to manually remind it. Many advanced players use World Info exclusively for durable worldbuilding and Memory only for current-scene information, keeping context clean and the narrative focused. Scripts are for players who want to introduce game mechanics: dice rolls, variable tracking (health, gold, relationship scores), conditional branches. You write JSON defining rules, and the AI learns to follow them. This is the deepest integration with the platform and requires some programming literacy, but it's how you turn AI Dungeon into a lightweight tabletop engine with procedural branching. A script might enforce that a character's "trust" score only unlocks certain dialogue options, or that rolling under 10 on a d20 causes a critical failure. Scripts aren't required—pure narrative-driven adventures don't need them—but they're there for players who want to blur the line between interactive fiction and structured RPG.

It's responsive, it understands the three input modes, and it will complete your narrative arc. The downside: Griffin is more forgetful over long stories and less inventive with description. After 20-30 turns, you might notice it repeating phrases or losing track of character details, especially if you're not actively maintaining Memory. Adventurer ($9.99/month) unlocks Wyvern, which is where most casual players land. Wyvern is significantly more coherent across long narratives, less repetitive, and more attentive to character consistency. You also get unlimited action points (the free tier caps you at 200-500 per month) and expanded context windows, letting your adventure grow longer without older scenes being discarded. For anyone playing weekly, this tier pays for itself in quality. Hero tier and above unlock Dragon, the flagship model, and unlock maximum features: largest context windows, most World Info entries, fastest response times, and access to experimental models. If you're running a 200-turn narrative with a dozen recurring characters and a richly detailed world, Dragon is where you feel the difference. The prose is more literary, the plot twists feel less arbitrary, and consistency across long arcs is much stronger. Most players find their home in Adventurer. It removes the action cap (the main friction of the free tier), and Wyvern is genuinely good. Unless you're a heavy daily user or writing at novel length, the step up to Hero rarely feels essential. That said, if you're doing multiplayer campaigns or running a long-form world with friends, the expanded context of higher tiers starts to matter—your complex World Info won't get pruned mid-scene, and responses come faster when multiple players are waiting.

If you're coming from Character.AI or Janitor AI, you're probably used to free-form dialogue with a single character; AI Dungeon is the opposite. Instead of chatting with one NPC in isolation, you're navigating a world full of characters and obstacles that respond to your choices. If you've played tabletop RPGs like D&D but can't find a regular group, AI Dungeon solves that by removing the scheduling friction and giving you an infinitely patient DM. Compared to NovelAI, which is geared toward solo writers using AI as a prose co-pilot, AI Dungeon is much more game-like. NovelAI excels at structured long-form fiction with image generation; AI Dungeon excels at turn-by-turn improvisation where you steer the narrative moment to moment. If you want to sit down and write a 10,000-word chapter with AI assistance, choose NovelAI. If you want to play a game where the outcome is genuinely uncertain and your choices fork the story, choose AI Dungeon. The platform also supports multiplayer: invite friends to a shared adventure, each play a character, and watch the AI improvise around all of you. It's not quite synchronous—it's more like a play-by-post style where you take turns—but it works for groups that want lightweight storytelling without complex rulesets. For players who've always wanted to DM but don't want the prep work, or who want to join a friends' campaign without learning d20 mechanics, this is the middle ground. Who should skip it? Players who want total privacy and local control should look at SillyTavern, which runs entirely on your machine. Players who mainly want to chat with a specific character should stick with Character.AI. Players who want visual novels or branching narratives with predetermined outcomes aren't the intended audience either. AI Dungeon is for people who crave emergent narrative—stories they didn't write and couldn't have predicted, shaped by their choices but genuinely surprising.