How did you manage to add the Infantryman animations to the inside of the Zombies, and make them work as well as his own, all together. This is very cool, I would like to know, it opens up many possibilities. Sometimes I saw some models, and saw that their set of bones is not identical, although the creature is the same, but the animations with the bones are different, and the two models have cool animations, and for example, I sometimes wanted, for example, in such cases as to combine animations, 2 different models by the set of bones, but I did not know how, and indeed I thought that it was literally unrealistic if you were not the creator of some kind of games, since these are literally different models and there is simply no way to add some animations from 1 to another.
But your example apparently proves (or I just misunderstood) that you can add animations from 1 completely different model, into the second completely different from the first model, and that it would work cool, as if the animations are native.

Or does this only work with Reforged models, but won't work with WoW models?