I tried to do a similar thing last year to datamine a gacha game's assets and somehow did it without knowing the existence of tools like IDA/Ghidra. They're using a custom db format that was XORed with a key. Iirc it was a bizarre format, it's actually an archive where each column is a file containing all the rows of that column. So a table is just a folder full of these files. Maybe it's a common thing idk. I got a partially working XOR key so I used ImHex to look at the partially decrypted db file and manually looked at the decrypted hex values to "correct" them.

I wish I read something like this article at that time!