Vertical 9:16 video, 5 seconds, one continuous shot, photorealistic Halloween makeup transformation. Subject: the person from the uploaded selfie, framed from the chest up and looking straight into the lens. Keep their real face, hair, skin tone and clothes from the photo in every frame. Setting: a dark room, one cool light from the side of the face, deep shadow behind, a hint of colored rim light on the hair. 0-1 s: the person's bare face, calm, sharp and fully visible. 1-4 s: thick, wet-looking black symbiote goo seeps out at the jawline and flows upward over one side of the face only. It stops at a ragged, spiky edge that splits the face along its center line, from forehead to chin. On the black side, a big white eye shape with pointed edges opens around the eye, and a long row of slender, hooked white fangs lines the jaw from the lip corner to the ear. Fine dark veins branch from the edge of the black across the uncovered cheek and along the neck. 4-5 s: the person tilts the head slightly and gives a slow, confident smirk, holding eye contact with the camera. Look: high-gloss black surface with bright specular highlights, half monster and half human. The uncovered half keeps the person's own skin, eye, brow and lips exactly as in the photo. Camera: steady, slow push-in, shallow depth of field. Variation: open with a hand sweeping across the lens; when the hand moves away, the half-face look is already complete. Avoid: blood, wounds, gore, masks, costumes, chest emblems, logos, text, watermarks, a second person, goo covering the whole face.