For transparent areas in the body3 and body4 textures, the alpha textures can be used with a color ramp node (for example) to make the black pixels transparent. These textures include a gradient (rather than simple pure black areas), so they are provided without transparency by default.

Other than the exceptions listed below, the alpha channel for each eye texture is identical, and is provided only once as eye_alpha. Similarly, the alpha channel for each mouth texture is identical, and is provided only once as mouth_alpha.

The eye_normal and mouth_normal textures include unique alpha channel textures (which are not identical to the standard eye_alpha and mouth_alpha), so these are provided individually as well. The main difference appears to be an increased amount of compression artifacts. Interestingly this only affects eye_normal and not eye_normal_B. It is unclear whether this is by design.