Lightning built by recursive midpoint displacement, so the bolt has real corners and real forks. Its own screen position lights the cloud deck by single scatter, so the sky blows out from where the strike leaves it. Every kick re-seeds the whole polyline.
Drawn with: a WebGL2 shader.
Reacts to and looks like: gpu, webgl2 and lightning.
Family: Visualiser.
Runs in your browser. The preview above is the same program the renderer uses.