Frostpunk is a very difficult survival city builder. You may be used to peacefully building a pretty town and managing resources, but this really takes it to the extreme. The earth has frozen over, and you've travelled to one of the generators that was set up in advance for this catastophe to last as long as you can. It's not a relaxing game, but it does really make you think. It's got an overworld where you can explore, send out scout parties and set up outputs, a research tree, and very demanding citizens. With striking visuals, a really clean UI and meaningful story choices, Frostpunk is certainly going to stick in the memory - even if you don't manage to finish it.