Where can I process raw iron and wood?

Raw iron can be made into iron bars at the forge, and raw wood can be made into wood planks at the carpenter.

What is energy used for?

When visiting an expedition island, you can collect building materials and other resources by expending energy. When your energy runs out, you will no longer be able to collect resources, and will need to wait for your energy to replenish over time.

Why can’t I harvest materials from larger trees or rocks?

Large resources can only be harvested by more than one player working together. You can see the number of players required listed when interacting with the resource. You can initiate the harvesting of the resource by yourself, which will send out a signal to any nearby players who may be able to help.