Choosing a writing style

Style here means how the sentences sound, not what the story is about. Genre goes in your premise. A cultivation novel can be told in plain serial prose or in an elevated mythic voice, and those are genuinely different books.

The six

• Web novel — clear, natural, modern English. Complete sentences of ordinary length, dialogue that sounds like people talking, very little metaphor. The default, and the right answer for most serial fiction.
• Literary — dense and interior. Meaning carried by image and implication; a scene can turn on something unsaid.
• Cinematic — camera-eye. Action, gesture and dialogue, almost no interiority; short paragraphs, hard cuts.
• Pulp — terse and punchy, with attitude. Short declaratives, dry narration, fast dialogue that hits back.
• Mythic — elevated and formal, told with the weight of legend. Long cadenced sentences and deliberate repetition.
• Dry & comic — deadpan. Calamity narrated calmly, trivia narrated gravely, and the narrator never enjoys its own joke.

Why it cannot be changed later

The style is baked into the system prompt, which is the shared cache prefix for every chapter of the novel. Changing it mid-novel would both invalidate that cache and — far worse — make the book audibly change voice halfway through. So it is set once, at creation.

If you want to nudge it without changing register, use author's notes in novel settings. Those override the style rules and can be edited whenever.