Deviant Artist and Halo fan Scourge07 combined his penchant for art with his passion for Bungie shooters to create a series of wonderful minimalist posters, one for each game in the series.
Well, each core game at least. I do not see a Halo Wars entry, nor do I see one for Spartan Assault, the top-down shooter for Windows Phone and Xbox Live. Genre-bending side stories don't deserve minimalist posters. The core series, however, is quite lovely when stripped to its bare essence.