Canvas 1024x1024 RGBA PNG, transparent except the mouth.

Style: match the base exactly: hand-inked plush illustration, dark-brown ink outline of the same weight as the base, soft flat shading, matte, no gloss, no 3D render.

Pose: bear faces slightly to the viewer's left; draw every mouth in that perspective, on the cream muzzle.

Placement: centre x=555, y=470, keep all mouth pixels within x 469..641, y 437..529; the top of the mouth stays below the nose (nose bottom about y 455), never covering the nose.

Scale: teeth are small and irregular, each tooth about 6-12 px wide, needle- or fang-like, inked individually, never an oversized blocky row in a glossy lens shape. Paint only in front of the face; nothing that would sit behind the head.

12 clearly different variants: 1 stitched shut (thick black thread X-stitches across a seam line), 2 jagged needle-tooth grin (dark red-black mouth interior, uneven yellowed teeth), 3 bloody vampire grin (two long fangs, blood dripping down the muzzle to max y 529), 4 cannibal mask (leather muzzle mask with vertical bars and straps that stop at the muzzle edges, worn brown leather with rivets), 5 smoking a cigarette (lit cigarette at the mouth corner toward the viewer's left, ember glow, thin smoke wisp rising inside the zone), 6 wide shark grin with missing teeth (gaps), 7 torn-open mouth with stuffing spilling out (white cotton tufts, ripped thread), 8 zipper mouth half unzipped showing teeth (brass zipper), 9 sewn-on button-and-stitch frown with one popped stitch, 10 drooling rabid snarl (green-tinged drool, curled lip of fur), 11 blood-smeared mouth chewing a severed thread with a cigarette butt, 12 grinning rows of tiny teeth with fresh blood splatter.

Colours come from the items (thread, leather, brass, blood, cotton, paper), not from the bear's fur. Output artifacts/mouth_01.png .. artifacts/mouth_12.png and artifacts/mouth.json: array of {"file","name","weight"}, weights summing to 100: 1:12, 2:12, 3:7, 4:5, 5:8, 6:11, 7:7, 8:8, 9:11, 10:8, 11:5, 12:6. Write artifacts/mouth_01.png .. artifacts/mouth_12.png and artifacts/mouth.json: an array of {"file","name","weight"} with weights summing to 100, rarer lower.