Create an easy Halloween coloring line-art illustration for young children featuring scene: Yarn Ball Playtime. Treat the scene description as a literal visual requirement. Every specific character, object, setting, or activity named in Yarn Ball Playtime must be clearly visible and easy to recognize. These scene-defining elements are the main focal points of the illustration and should be shown prominently. The stars of every scene are a small trio of adorable Halloween animals: a playful black cat, a friendly round-bodied bat, and a cute smiling spider with a small round body and short simple legs. Include at least two of these three animals in every scene, drawn large and expressive as the main characters, and give the spider a clearly happy face so it reads as sweet rather than scary. A simple spider web, when present, is drawn as a large open decorative shape with thick simple lines. At most one classic Halloween character, such as a witch, ghost, or skeleton, may appear in a supporting role, kept smaller and secondary to the animals, or may be omitted entirely. Simple Halloween accents such as a moon, stars, a fence, autumn leaves, or a single small carved pumpkin may complete the scene; when a carved pumpkin appears, keep it small and secondary. For the scene "Spider Web Trampoline," show a large round web stretched like a trampoline with one animal mid-bounce above it and the others cheering. For the scene "Follow-the-Leader Night Flight," show two or three bats flying in a playful line across the sky while the black cat walks along a fence below, following them. For the scene "Cozy Web Hammock Nap," show the spider proudly beside a small web hammock strung between two posts with the black cat curled up asleep inside it. For the scene "Leaf Pile Pounce," show a big pile of large simple autumn leaves with the black cat pouncing into it and a bat flapping above, scattering a few leaves. For the scene "Moonlight Fence Singalong," show the animals in a row on a fence with their heads tilted up toward a large moon, mouths open mid-song with a few simple music notes in the air. Keep the scene simple, spacious, and easy for young children to color, using only a few large, clearly separated elements, broad open coloring areas, generous white space, and minimal detail. Present the line artwork itself directly as the image: a flat, straight-on digital illustration filling the canvas, with the canvas edges themselves forming the outer limits of the artwork. Use only black outlines on a pure white background, and keep every enclosed shape completely unfilled with a bright white interior. Every visible element, including lights, windows, pumpkins, ghosts, decorations, trees, shrubs, bushes, bats, and hair, is rendered as crisp black outline line art with bright white interiors, so the entire illustration reads as a pure black-and-white line-art image. Create a true edge-to-edge composition: a few large scene elements may naturally continue beyond and be cropped by the four canvas edges, while the main characters and main activity remain clearly visible within the canvas, leaving the canvas edges visually open rather than enclosed. Keep all potentially writable surfaces plain and unmarked; communicate everything entirely through characters, objects, poses, and actions. The finished artwork contains only pictorial black linework and white coloring space.