From the publisher: Were you ever playing a scene in your game, and suddenly you wished you had a GM that told you what happened just next? Right after your characters took actions, you asked some questions, you wanted to look at the GM's face and see what he came back with. The Scene Unfolding Machine (SUM) is a GM Emulator that helps you come up with content during your scenes. Ask the virtual GM their next actions and reaction, after our characters took their actions. Figure out what happens next when we get stuck, and are no longer sure how our GM-less games move forward.