stretchy spine https://vimeo.com/214380164/0dc5a17147
create ik spine
route on curve
node editor
bring in curve
arclen -ch 1 play to make curve info
create md node
copy curve length into md input 1+2
operate divide
attach md to curve info input 1x
connect editor
md left joints right
output x - scale x
skin joints to curve
create 3 new joints to og joints
head mid end
skin
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