I dug up this character from a backup drive. I made this in 2001. Organic forms had to be made with nurbs and extra care needed to be taken to make sure the surfaces didn't pull apart during animation. Lots of tricks had to be used to join surfaces and create hidden blends. Strangely rigging and animation tools haven't advanced at nearly the rate of modeling tools. Fun flash back in time.
tough job to blend the surfaces together
Below are some rig tests. Rigging hasn't changed too much in the last 10 years. Tools to do the job have been streamlined, but we've been moving weighted points based on simple armatures for long time. Dual quaternion skin deforms help, but muscle systems have stayed proprietary.