At the start of this mode, you are taken to a lobby area containing most special characters in the game. You are then allowed to add up to 4 special characters to your party. The area also contains two buildings: the Familiar Lounge, housing every custom character you've created (and some random pets), and the Experimental Hut, containing ordinarily nonplayable characters, such as the Grim Reaper, as well as exceedingly rare characters Lil' Sam Byool and Oscar. In addition, you are granted some extra starting supplies compared to other modes. Pick wisely, as the amount of zombies is increased to 300%, which can easily overwhelm an unprepared player. Bandits will also be more cruel.
- Before the August 2019 ILEUM Part 2 update, this mode did not count towards win streaks.
- Mecha Mountie is among the NPC recruits from the Experimental Hut. He attacks like how he does at Canada's Border. Before the June 2019 ILEUM Part 1 update, he used to fulfill Mason's checks and periodically kill off party members due to a special character ID assignment quirk. Additionally, Mecha Mountie's sprite would become that of Mason upon quitting and reloading the game.
- Familiar characters do not count towards the four character limit, and their starting inventories (and anything they can't carry) will dump to the trunk upon dismissal as usual. Additionally, if they are carrying any supplies due to their perk, they will be added to the trunk upon entering the lobby, without having to recruit them.
- Recruiting a character in the lobby will not reveal any of their stats, even those which are revealed if encountered normally.
- Certain characters, such as Herman, are not (yet) present in the lobby.