I went to log in today, said something about it being out of sync...I thought it was just something to do with screenshots or whatever? I log in and I went from level 40 to level 30 and lost all my good weapons?
What the hell is this crap? Is this steam to blame or Borderlands 2, this is garbage.
Steam Cloud is a function that steam has implemented for a while now (over a year) where it basically copies your saves to its servers, so you can use the same saves if you change computers.
When you got that prompt, it's because steam noticed that the saves on your computer and the saves on the steam cloud did not match. So it asks you which one you want to keep. They usually also tell you when the last time each of them were accessed. (Day-wise)
So if you played on your home computer Saturday, then you try to launch the game at work (or anywhere else) on Monday, it sees that your work save doesn't match (because you last played at work on Friday, for example). So it asks you which of your saves you want to keep. The ones from Friday, or the ones from Saturday.
You would usually choose the latest one (in this case, Saturday) since it's usually the most up to date one.
If you've only ever played at home and you got that notification anyway, it means that it failed to upload your saves at some point (probably internet connection problems, or steam servers connection problems) so it still sees that discrepancy between your saves and the ones on their servers, thus they ask you which one you want to use.
It sounds like you chose the older ones, so it rolled you back. Once you've chosen this, there is no way to "fix it". You screwed yourself over and now you have to start over from where that save was.
As others have said, pay attention to popups you are given.
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