goblin with corroded copper sword and corroded copper armor, stylized low poly game asset, flat shading, faceted surfaces, solid colors, optimized for real-time rendering with ~500 triangles, single mesh, clean quad topology, neutral A-pose facing forward, flat PBR shader with muted green skin, rusted copper sword and armor highlights, export as glTF format; avoid high-frequency noise, complex UV layouts, and unnecessary subdivisions