Dannager
First Post
So the easiest thing to envision, that would cut you off from both local and cloud storage, would be a criminal invasion of a system, in order to exploit the local system and co-opt any and all storage that's available. I've seen it from a Windows system, from which a Unix-based production printer was exploited over a network. The PC was left unusable while the passwords to the printer's storage were altered, locking out legitimate users, so that it could be used to store illicit files.
This is, at most, a temporary inconvenience (at least as far as your D&D stuff is concerned) that can be resolved via simply getting in touch with your cloud storage service and explaining that your system was compromised. Any major cloud storage provider will be able to restore access to your account and reverse any changes made to your stored data in a relatively short amount of time.
Meanwhile, if you've stored your data locally in an unconnected media (external hard disk drive or portable memory), it's likely that you'll have no problem simply pulling it up on an unaffected device.
I was hit by a rootkit two years ago. Thanks to responsible backup handling, I lost nothing important and had secure access to all my online accounts and my system itself restored within two days.
Now, in the event of criminal invasion of your home that results in your physical material getting stolen (granted, I've never heard of thieves breaking into a house to steal D&D books, but I have heard of thieves breaking into a car to steal them), good luck getting the police and insurance company to fully resolve your case in that kind of time frame.