Copy protection for the game required the user to have access to the map and comic book that came with the game. The comic book gave the keys to solving a cryptogram in the game as well as navigating the catacombs (with the map). Without the comic the cryptogram is still fairly easy to solve. Even with the comic and map the catacombs are nearly impossible to traverse.
Infocom's famous 69,105 number is used in this game to refer to the number of leaves contained in the sack found in Cleveland, Ohio.
Designer Steve Meretzky aimed to have his previous game, A Mind Forever Voyaging (1985), generate incredible controversy over its political commentary on the conservative policies of the Reagan administration. After it generated no controversy at all, Meretzky "decided to write something with a little bit of sex in it, because nothing generates controversy like sex."
One of the software trinkets (called "feelies" by Infocom) was a scratch and sniff card with odors associated with the game. One such odor was, of course, leather.