Create a 3D Roblox-style classic horned helmet accessory. The helmet should have a bold fantasy design with two large curved horns, inspired by classic Roblox avatar accessories. Use a black main body with dark purple and bright purple details. Add glowing purple accents, engraved patterns, and metallic purple trims around the edges. The horns should be black with subtle purple energy lines or highlights. Make it look like a premium Roblox UGC item: clean low-poly style, sharp shapes, symmetrica