Does anyone know how to make an enemy like this?

it's beautiful thank you.

Lots of nice examples! Think there is a lot of room for different approaches, it just depends on what look you're after.

Here's a test of doing the body with rope physics. It also adds a stiffness to the rope to make it try to stay straighter. Looks like the dragon is struggling against gravity now, so that was satisfying. Also added a knockback when it shoots fire and as a side effect the body gets a jolt that goes through it.

dropbox.com/s/gvfmn6eohn2lojt/bone_snake.capx

that bone snake is from another level, thanks for your contribution, it's worth making a boss with it.