You were lucky to find a planet filled to the brim with resources. But in each barrel of honey there is a small spoon of tar and on this rich piece of land there is trouble - its inhabitants. The planet was chosen by zombies and, as soon as twilight approaches, the ghouls go hunting. So the whole light day you have to work hard, extracting resources, parallel building the walls. But this is not enough to install weapons, minify the approaches in the database. Connect mines for the extraction of minerals among themselves in order to constantly replenish the reserves. Base in Yorg. io improves to level 7, and then you can upgrade the remaining buildings.