Prototyping on Paper

Here's a snapshot of my latest doodles which involve one of my many side projects on the game. Can you tell what it is about? Hehe, I don't want to reveal everything I do, but some obvious ideas ? ... My sister convinced me to post more of my notes (I'm no good at drawing) and I'm thinking to release a few periodically, if that's something you'd be interested in?

I use these a lot to visualize things on paper first and to discuss with the others. That one, for example, I sent to my artist. Drawing ideas on paper, rather than prototyping them, often gives me more time to delve deeply into the design elements.