As the Thief, I was carrying a Dragon Gem to stash, but when I got back to base, the cave did not have any treasure chests left. Now, the rules make it clear that the component limitation is intentional. I am asking to be certain that it applies to this situation as well. If the Cave has no treasure to exchange for a Dragon Gem, is the Gem just worthless? If you open a vault when the Cave has no treasure, is the Vault empty?
I think yes. I think the component limitation line makes this rule pretty clear, but I thought there was a chance I missed a clarification somewhere. Thanks!