Some friends and I have been doing Inktober on a Discord server. We made a prompt list with bonus "modifiers" you can add to the prompt for extra points.
I'm trying to spend a short amount of time (about an hour) and use minimal pencil construction. Trying out rushing headlong into new and complicated ideas. As such, there's plenty wrong with each of these, but they worked out as pretty good art EXP.

October 4th Prompt was "Highway Robbery". I wanted to do something really oblique, so here's a flying saucer robbing a cow off the back of a cattle truck.