The Universal material is used to get substance maps and PBR outputs into OctaneRender. Substance Painter and other engines map perfectly to this material.
This material blends between dielectric and metallic with a metallic parameter 0 to 1. When compared to other materials, the Universal material is equivalent to the Metallic material when the Universal material's Metallic attribute is set to 1.0, while it is equivalent to the Glossy material when the Universal material's metallic attribute is set to 0.0.
The Universal material is designed such that it follows after the workflow in the PBR model, since the Metallic material falls short of the metallic maps and roughness maps that are commonly derived from Substance Painter and other tools. It handles dielectric material (diffuse and glossy BRDF) and also metallic material (glossy BRDF) with assumed IOR or custom IOR for both dielectric and metallic surfaces.
In this way in a single material one can obtain, refraction, reflection, sss, emission, coating, transmission.
In this example, there are emission and specular but It's not a mix material.