11-bit studios has announced via a dev diary on their YouTube channel the long-awaited expansion to Frostpunk titled Endless Mode is finally right around the corner after releasing its difficult Survival mode in June earlier this year. Karol Zajaczkowski stated during the video that the reason the expansion took longer than initially expected because they decided to put much more content in it. The add-on should be available within the next couple days for free.
Within Endless mode, there are two sub-modes: Endurance and Serenity. Serenity allows you to fully focus on just building and growing your city. Resources will be plentiful and the weather is more forgiving.
The Endurance Mode is much different. This mode is designed for more of a challenge. It will include randomized events that will turn off in a couple days.
If you would like to watch the video yourself, which goes into much more detail on what Endurance and Serenity entail, the dev diary is below. Frostpunk is currently available for PC.