If the mask geometry is made from M3's head, you'll have to encode it with M3. (RTE would be best, since there's an RTE encoder/decoder utility for both Windows and Mac). If you made the mask geometry yourself, in a modeling applications, there's no need to encode. The morphs do not change anything about the encoding need. If your mask is cut out from M3's head, the morph deltas are from M3 too. But it won't be possible to extract them to recreate M3's head morphs, since the mask only partially covers the head, the number of vertices is different, and so is the vertex order. It might be necessary to encode the mask with multiple source files; not only M3 but also his head morph .pz2 (the InjDeltas ones). And if you made the geometry yourself (and created the morphs using The Tailor or the cloth room), the morphs are yours and you are free to do with them as you like. The M3 morph deltas may be a catch. I'm not sure if DAZ allows using them. You'd best ask DAZ.

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