under any animated model lies a animation skeleton. This allows the animator to move the model. Making walk cycles and various animations for the character or monster. We created one of these skeletons without a model over the top, editing it to have various proportions and using the tools in 3DSmaxx to create a walk cycle that went around various obstacles like stairs and duck under poles.
Here is a screenshot from my first walk cycle, walking over some boxes of various sizes:
I hope in the future we can do this once more with our own models placed on top of the skeletons.