I have no idea how to get the keys that let me unlock new things. I thought we could get the new keys from leveling up, but i don’t see any from my max level characters. Additionally, when I level up those characters it says “Chest Unlocked” but what chest is it even talking about? What is even going on?
In the main menu you go to the “Vault Card” tab. Each time you level up your card you’ll unlock a chest that you can open. In these chests you can receive rewards such as normal keys (used to unlock rewards in the purple reward tree thing on the right), you can get Diamond Keys (which you can use to access the Diamond Loot Room), Eridium (yuck), or any of the items on the purple reward table thing.
If you look at the bottom of the “Vault Card” tab, you’ll see options; I’m on ps4 so it’ll say something like "Press Square to Open Chest (3 available), these are the chests that you receive each time you level up your vault card. Not sure what buttons are for the Xbox or PC but if you read the bottom of the screen it should tell you.
Good Luck and hope this helps.
“Level up” in relation to Vault cards applies to a special experience bar for those cards only; it has nothing to do with normal character leveling, or Guardian Rank leveling.
Diamond keys are shown on your Inventory tab, like your Golden Chest keys. The keys listed on your Vault card are different, used for acquiring Vault Card items.