地球末日:生存 – What are bricks for?

You probably noticed a new resource among the rewards of the season and recipes for the refined melting furnace – «bricks». They can be used to upgrade the floor and walls of the base to level 5. So your base will look like a real impregnable fortress, but you can only find resources for crafting in the most remote places – on island locations and swamps.

地球末日:生存 Last Day on Earth: Survival Game GUIDE