I was making two different games at once, spent a few months on both. Then, my drive figured out it was a good time to corrupt and went ahead and did so. Couldn't access the drive, so lost both games. Luckily, I found a software that decompiles built Unity games into a project folder so I got back one of them (it was shared on itch, so I could get the built version). The other one I did have a built version but it was on the drive as well.
Lesson for life: back up your stuff!