A muscle rig is a rig that has muscles under the skin to make deformation look a lot more realistic. As he moves the muscles are controlled by SKD's and expand and contract pushing and pulling the skin on the outside.
I plan to add muscle jiggle soon to add a little more realism to the character. Muscles are very bouncy and a creature this size would probably have a lot of jiggle while stomping around.
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Richard Cheek
https://www.freelance-animation.com
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