it is too difficult for me, I give up it.

Thank you, Richard.

Ok. We will try to create some example of this (or create helper classes to simplify the creation of this type of systems) for the 4.1 release, so keep your eyes open for that.

Ultimately though, it is a rather complex thing to animate skeletons procedurally in an optimal way. The only way to make it dead easy is to limit the system (or build it in such a way that complex, more realistic use cases require sub-optimal workarounds) so it’s not an easy nut to crack.