At the moment VXGI Specular only uses direct light to create reflections. That being said, having most surfaces in your scene covered in direct light is required to get proper reflections. Some scenes may not even need special changes, but most of the time, you will need to adapt your work flow slightly. Setting emissive to a value between 0 and 0.1 is very effective on metallic surfaces in particular, as it completely removes “empty” reflections by adding directly to the base color. In scenes that don’t require heavily controlled lighting, you can use dim ambient point lights set to movable, which is probably the ideal setup for games that don’t using any static lighting, because it causes low end devices that can’t support VXGI gain some ambientnce as well. These are just a few suggestions based on my own tests; play with it a little and please, report any findings you make! 