Your Supply Depots and Miners aren’t just some beautiful buildings to show off. They are capable of harvesting important minerals such as Lumen from the planet’s surface and finding invaluable loot boxes from the depths. Building units and structures, researching upgrades and using power all cost you Lumen. When you select an item or action that requires Lumen, that amount starts being deducted from your vault until the full amount has been paid.
You begin your game with enough Lumen to spend on building some basic structures. However, to continue your journey, you must acquire more and more Lumen. If you choose to perform a task that requires Lumen, but run out of it, that task is put on hold until you earn more.
To acquire more Lumen, you must build Supply Depots, Apartments or Drop Zones. Supply Depots will harvest the surface of the planet in search of Lumen. There are some places that have a large amount of Lumen on their surface. If you build your Supply Depots on those surfaces, it will naturally speed up your resource gathering.