xbox/tools/embed-spine.mjs carries spine.mjs + actions.mjs into a sealed block in oskiewar.js (each module in its own scope, one global spineBody); a test fails if it drifts from the lab source. Each park player gets a body driven by the game every tick: position, speed, heading, air, board/kart, crouch, strikes, hits, landings, grabs and chalk. The body is the pose (renderers, hitboxes and items read it unchanged) and the torso is drawn along the rope in the SDF and mesh renderers. Spawns and deaths roll a new body from the park's seed. The spine now runs through the skull with firm neck joints, so the head rides the spine. Reaches crouch for depth and hinge for distance, hold their effort, and measure from a fixed reference (the old one made the body bob); frames build from the right axis so a folded body's shoulders don't flip. Driven roots carry most of the game's travel so full speed doesn't fold the rope. Rollback netplay keeps the old rig for now. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>