Last night I setup a new dimension that contained cities to give players yet more variety of worlds. However, it was too easy for players to run around collecting resources from the various structures on the world. My attempts at increasing the spawn rate of zombies was thwarted by the slabbed pavement that made of the majority of the cities streets. Monsters and animals don't spawn on slabs.

The city world has been re-adjusted to make traversing the world and collecting resources a bit harder. It is always night and never stops snowing. It uses a similar temperature system as the ice dimension but has a slight change. Being inside some sort of shelter will halt your temperate bar, allowing you to set up a heat source and or claim a structure as a means of recovering from the harsh cold. The cities themselves are still there, just buried under snow. Lots of snow.