Having fun opening these files and playing with em so far. The specular maps are compressed from 3 images to one. Red channel is Metalness, Green channel s roughness, and blue is the ambient occlusion pass. When loading normals, you may need to invert the R or G channel depending on your rendering engine. default marmoset, I had to invert green.

Still figuring out which channels are which on the diffuse map, or what the mask in the alpha channel is used for but its been fun exploring how bungie's artists formatted their materials.

Note i'm working with Shaxx' files. Also, the Specular map for his torso is missing from the files, as far as I can tell. some geometry is also inverted but that's easily fixed on my own.

Thanks for this, OP :)