A comparison, between Tentacle Creator, Rotation Spring and Rotation-Tentacle Spring.
The first is a Procedural animation tool for tentacle motion.
The Second, Is like a spring, but on rotations, you can apply it on a bone chain. It creates delay rotation following translation and rotation of the Master or its parent.
The third is a combination of these two tools.A Spring delay rotation added to a tentacle motion.
See also : Tentacle Creator