Idea for an expansion that adds a final "lightning round". After proximity hits 99, escaping players must make a break for it. A few(6-10) pursuit cards would be included, along with many new cards. Players not trapped in the building secretly bid DF tokens and the pursuit card is revealed. the player who bid the least loses extra DF points with a severity based on one or more of several factors:alarm dial, players who were captured, rooms left unexplored, NPCs/lab workers in play, etc.). depending on pursuit card, player who bid second least may also suffer a lesser penalty, even 3rd least and so on. alternativly, players who bid below a certain amount might all take a penalty, player who bid below a certain amount may be considered to be "captured" and automatically lose.
Hot Wheels:Several items you find during the infiltration help you out in the chase, maybe reducing DF loss from pursuit(like the codekey to fastest car in parking garage). Perhaps you find a file on their Security Protocols; allowing you to peek at the pursuit card. If you can crack the Dispatch Encryption, you can look at, and choose whether or not to replace, the pursuit card!
Who's turf is this?:At setup players reveal 3 pursuit cards, then randomize them to create the "pursuit deck" for that game. this way no one is caught completly unawares as to who is coming after them, but still may not know for sure.
Dead Drops:players who escape early get a head start by putting one DF token in a "dead drop", each turn before proximity hits 99. dead dropped DFs are protected from pursuit cards. If all players ecape before proximity hits 99, subtract proximity from 99 and divide that by [3+alarm], always round down. each player gets that many additional dead drops before the chase. Bit too mathy maybe, but thematically sound.