for my third blender experiment I used a displacement modifier with a voronoi texture on a subdivided plane. The displacement modifier is controlled by a keyframed empty to make the texture move and change.
you can download the blend file here
I'm still not satisfied the shadows created by eevee - a decent shadow setup seems to be more complicated than i expected it to be - especially when animating things. Will have to do some more experiments on this
blender 2.80 experiment 2 - array modifier
blender freestyle sketchy line howto
blender eevee with sketchy freestyle lines
tree animation with blender eevee and freestyle