This week, for one of the challenges, you will have to search supply drops! These supplies are the famous llamas that appeared in patch 3.3.
At the moment there is no information about this new way to get resources. They appear randomly, but if you find one, you should be happy! Each llama gives 500 wood, stone and metal, several hundred balls, healing... In short, enough to meet your needs! Note that it seems that llamas only appear in outlying areas.
Our guides on the challenges of the week