The theme this month is "Game Mechanics"
This theme deals with anything in a game (video or tabletop or other wise) that has a mechanic or rule that could be exploited for art purposes.
Examples: You run out of stamina; roll a nat 1; what happens to your mini's when you fail a charge roll; you joined the local game store's strip-dnd game.
As a bonus thought, I was thinking of adding a UI element to the images, not a requirement, but maybe that helps the gears turn.