Fan Fic is where I started and while it taught me some bad bad habits it also taught me to become the kind of pantser that I am now. Thinking on my feet and changing story line direction by playing the what if game.
How about if my characters did this? What would happen if there was an X here... What if I killed one of my characters? What about if X did this to Y, how would Z react?
I don't know about other writers, but I am always playing the What If game when I am writing. It's how I write, throw a situation, or a place, add in a character, add another one in, shake and see what happens. So when I saw this I thought.... ooohhh.... what a cool thing... shuffle and pick random cards and you could end up with a whole new thought provoking direction than you had before.
These were specifically created for fan fiction writing, but ignoring the purple cards which seem to be fan fiction specific I think this could be a really interesting experiment in writing for everyone...