The VG Resource

Hi people, 
I have a small issue with the texturing of a model from "Alice Madness Returns" on PC. On a couple of occasions, textures files include the usual DM, SM and NM versions, but also a fourth whose file name ends with "Mask" or "Msk", and I have no idea how to use those on the models. They consist of a black and white version of the textures, with the details drawn in pure white on a black background (I added an example as a joint piece right below). Could someone tell me how to use it? Worst case scenario, I could leave it aside while working on the model, but including it in the files when i submit the model, in case it could be of use to whoever is interested in the model in the future.
Thanks in advance for your insight!

[attachment=14567]

There isn't any way to know what this texture mask is being used for with no model and textures / game screenshots to compare it against.

It could be used for almost anything, to add 1 color or multiple, for transparency, etc...

Noted, I'll get back with more details asap!