Varicose effect - https://forums.getpaint.net/topic/112488-varicose-2-ymd18-02-20/
I may or may not have seen that in Inkscape and G’MIC, but pretty sure seam carving utilize very similar technique to the varicose effect. So, I’m looking to see if there’s anything similar to that.
I did found lightning though. I could use that to create lightning brush for Krita.