A few years ago I had the pleasure of designing the world of Abyssal Arts's game, City of the Shroud (http://www.abyssalarts.com/shroud). It was a small-scale, but ambitious, indie title.

The story portion of the game was essentially a visual novel, so in addition to design, I made illustrations to be used in-game. The critical event of the game is when a mysterious shroud falls over the city, trapping everyone inside. As a result we needed 2 versions of each BG piece, pre- and post-shroud.