Keep exact 128x128 4x4 tile atlas, every geometry edge an...

Keep exact 128x128 4x4 tile atlas, every geometry edge and alpha silhouette and tile position unchanged. Add visible dark cracks and small chipped brick corners to each existing wall strip; these are half damaged but still connected walls. Preserve all connections to each tile edge, fixed overhead light and gray blue palette. No rotation, no displacement, no new objects, transparent background, crisp pixels.