I've known about it since day one... maybe two... I admit though the only reason i know of it is because i got the game guide when i got the game. Not because it was useful (at all) but i i have a book shelf with all the hardcover game books and figured it would be a good addition... The only place i really use the cover though is on the mars strike with Valus, I like the 2nd story left side barricade for some reason... never use it anywhere else