The Timekeeper's Journal

Feature Spotlight: The Living World (NPCs, Part 2)

No more characters talking through walls, and no more single friendliness slider: dynamic scene casting, trust, fear and intimacy, and changing moods.

The Timekeeper · 2026-09-21

Following last time's post about giving AI characters a backbone (refusal anchors) and a voice of their own, I want to tackle two more big immersion-breakers in AI RPGs: telepathic characters and flat emotions.

Here's how Hourglass 3.0 makes NPCs obey the laws of physics and psychology.

Dynamic scene casting

Have you ever been talking to someone in a tavern, walked out into the street, started a fight, and had the tavern character suddenly chime in with advice?

Because most AI games rely purely on the conversation so far, if a character's name came up recently the AI still thinks they're relevant. Characters end up talking through walls or teleporting to wherever you are.

To fix this we built dynamic scene casting. The Ledger records whether each companion and NPC is actually present in the scene. If they aren't, their details are removed from what the narrator sees, so it can't let them speak: as far as it knows, they aren't there. You only interact with who is actually in the room.

"It is much safer to be feared than loved, if one of the two has to be wanting." — Niccolò Machiavelli

Trust, fear and intimacy

Most games treat relationships as a single "friendliness" slider: give a gift and it goes up, insult someone and it goes down.

People are far more complicated than one slider, so we track relationships on three separate scales from 0 to 100:

  • Trust: do they believe what you say?
  • Fear: are they afraid of what you can do?
  • Intimacy: how close is your personal bond?

That allows for far more nuance. A corrupt 1952 Chicago beat cop might have 90 fear, 10 trust and 0 intimacy: terrified compliance. He'll do what you say, but he'll snitch the moment you show weakness. A spouse might have 90 trust and 90 intimacy, but 0 fear.

Changing moods

To make sure the AI actually uses these numbers, every NPC has a demeanour. Each turn, a background model updates a one-to-three-word snapshot of their physical and emotional state, such as "trembling, defiant" or "relaxed, amused". That forces the storyteller to update their body language as things happen, instead of leaving them stuck in one emotional state.

Next time I'll wrap up the series with Part 3: how to actually get past those ironclad refusal anchors using social puzzles, leverage and off-screen agendas.

Have you ever had an AI game ruin a dramatic scene because a character teleported into a room they had no business being in? Tell us on Discord.

In the manual: How People Behave · Relationships

Thanks for reading. See you in the past…

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