X-muscle System Best blender muscle Addon

X-Muscle System is advanced, physics based tissue simulator for Blender.
https://blendermarket.com/products/x-muscle-system

X-Muscle System is an add-on designed for rapid muscular system, tissue and other organic object creation and their physical simulations. Its main purpose is to help visualize better skin surface deformations according to volume preservation of the body muscles, fat and even skeletal bones. Add-on lets you focus on the design, creativity and to significantly speed up the workflow with extremal learning curve.