Inventory management is a mechanic in most games that you have to learn to live with, or you'll be in for a hard time. Black Skylands is no different. You need to access storage to be able to dump in supplies so you can access it from another location.
The warehouse in Black Skylands is basically neverending storage that can hold 1000 items. Eva has no personal storage/inventory meaning you cannot hold any resources on her. You have to manually pick up an object or resource and walk it to the nearest warehouse to deposit it by pressing the button prompt that appears.
Once inside, the resource is safely stored, and you can access it from any warehouse that you find in the future. But you do have to find the warehouse in another location to do this. To access your warehouse, just go near it and hit the button prompt that appears.
While holding something, you cannot fire a weapon or use a melee attack. You can only use your grappling hook. This is troubling if enemies are still nearby, and you have found a resource quite a ways from a warehouse.
On your airship, you have a cargo hold, and from there, you can access your cargo hold, which is handy for all your ship needs—cannons, repair kits, and the like—and to the warehouse, with the option to transfer between the two.
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