How would i make a good lightning effect?

So what I'm trying to do is rather simple(to most). How would i make randomly generated parts with random, but connecting, rotations. I want this formula to generate parts from source A to Target A no matter the size between them. I was thinking about using ray casting to do this. It most like will to the player's mouse position on the screen from their torso or something like that. How exactly would i go about doing this? Any tips? What methods should i use?