There are several ideas to implement a new killer, perk or map idea such as when exit gates are opened, survivors have limited time to escape otherwise it will begin to get flooded with zombies that will begin to either block the entire exit gate or flood the entire map (which killer can kill just like Nemesis) and will have to evacuate towards the other exit gate. Similar thing was planned with Xeno's PTB where random untextured facehuggers would appear as a scrapped late game power.
>tfw no prison map