higgsfield-facs

# Higgsfield FACS Director Direct a face the way an animator does — by **muscle**, not by mood. FACS (the Facial Action Coding System) names each facial movement as an **Action Unit**: `AU12` is the lip-corner puller (smile), `AU6` is the cheek raiser, `AU4` is the brow lowerer. Put those codes in a Seedance 2.0 prompt and the model renders the corresponding action. It is the highest-resolution facial control available on the platform, and it is where forced smiles, uncanny faces, mixed emotions, and honest micro-performance in close-up dialogue come from. > **This skill is a facial-control layer on top of `../higgsfield-seedance/SKILL.md`.** > Every FACS prompt is still a Seedance prompt — six-slot formula, Prompt-Craft > Laws, preflight linter. FACS only changes *how you specify the face*: AU codes > instead of (or alongside) emotion words. It is the muscle-level case of the > Voice Rewrite rule "describe physics, not emotion." ## QUICK FACTS *Routing aids — read the linked sections for the actual rules.* - FACS = facial expressions as **Action Unit codes** (muscle movements), not emotion labels; you write the codes into the prompt [→](#what-facs-is) - **Provenance split:** the AU vocabulary is standard human science; Seedance's *interpretation* of codes in a prompt is **[EMPIRICAL]** — high success rate, **not a guarantee** [→](#provenance-and-the-not-a-guarantee-rule) - **Plan first.** Decide the 3–4 expressions you need → generate a FACS sheet for *only those* → write...