Lunafic vs Sudowrite
A story you live in, or a document you work on.
Both products help you write fiction with AI. They are built for opposite relationships with your story. Here is the honest split so you can pick yours.
The fair start
Sudowrite
A serious writing tool for novelists who work in a document. Craft features like rewrite and describe tools, brainstorming, and a story bible you fill in by hand. If your goal is finishing a manuscript for publication, it is built for exactly that.
Lunafic
A story world you step inside. You play your main character, the AI plays the entire cast, and every scene becomes a chapter you keep. Built for writers who want to experience the story while writing it.
We know this category firsthand. Lunafic V2 was built as a direct competitor to Sudowrite, a professional writing tool for writers. Then we moved to our core, playing inside stories, and V3 kept the engine while leaving the document workflow behind.
The core difference
Where you sit relative to the story.
Inside the scene, or above it
Sudowrite keeps you above the manuscript, running tools on paragraphs. Lunafic puts you inside the scene as your character. The AI never plays you and plays everyone else.
The bible is read, not just stored
A story bible you fill by hand is a reference document. Here the world bible is read by the AI before every reply, and layered memory carries what actually happened across chapters.
A story that persists
Chat-style sessions scroll away. Chapters stay. You can reread the night from chapter 3, branch from it, or keep writing it next month.
Side by side
Relationship to the story
Sudowrite: You work on the document
Lunafic: You play inside the story
Who writes your main character
Sudowrite: The tools draft and rewrite with you
Lunafic: You do, always. The AI never plays you
World and lore memory
Sudowrite: Story bible, filled in manually
Lunafic: World bible the AI reads every reply, plus layered story memory
Output shape
Sudowrite: A manuscript document
Lunafic: Chapters of a story you can reread and branch
Multi-character scenes
Sudowrite: You write all characters yourself
Lunafic: The AI plays the whole cast in their own voices
Best for
Sudowrite: Finishing a novel for publication
Lunafic: Living the story while you write it
The honest pick
Pick Sudowrite if
You are writing a manuscript you intend to publish, you want craft tools over paragraphs, and roleplaying inside the story sounds like a distraction.
Pick Lunafic if
You want to be in the scene as your character, you want the cast played back to you, and you want the story remembered chapter to chapter.
Questions people ask
Is Lunafic a replacement for Sudowrite?
No, they serve different writers and different moments. Sudowrite helps you manage and polish a manuscript you are writing toward publication. Lunafic is where you live inside the story world between and during drafts. Some novelists use both, a document tool for the manuscript and Lunafic for the world. Knowing which one you need is the honest first step.
Does Lunafic have rewrite and describe tools?
We removed most document-era tools on purpose when we became a roleplay-first product, because they served a manuscript workflow we no longer aim at. Inline editing exists so you can fix any line, and the craft focus moved to the scene level, where direction, memory, and the cast matter more than word-level gadgets. What stayed is everything a scene needs.
Can I export what I write?
Yes, you can export your work at any time. Your story belongs to you, it is never used for AI training, and leaving with your full text is always possible. Export covers the chapters you wrote. We would rather you stay because the story works, not because the door is locked. Your words never live in a locked box here.
Which is better for long stories?
They have different strengths. Sudowrite helps you manage a long manuscript with craft tools over paragraphs. Lunafic keeps a long story consistent because the world bible and layered memory are read by the AI continuously, so chapter forty still agrees with chapter four. For roleplay-length stories, that consistency is the whole game. Pick by the job, not by the brand.
Try the story side.
Play a character inside a world tonight. Free to start.
Zero stories used for AI training.
