I’m not sure what happened, But the map I spent several weeks putting together sort of… exploded? I don’t really know. Please help, I’ve tried rebooting and resetting the tileset image and reloading it but I can’t get it to go back to the way it was.
Hey @SneakySnack, welcome to the Tiled forums!
Unfortunately, I don’t understand how this can happen at all. It looks like the map was manually vandalized?
Did you really spend several weeks working on a map but have no backups or any kind of version control that still has older copies of your map? 
It certainly wasn’t manual. I was in the process of working on it when it happened.
And unfortunately not, on the backup front. This is for my very first game, and there are a lot of mistakes and best practices I’m learning about as I go. I didn’t have the foresight to make separate backup files, though you can bet dollars to doughnuts I will from now on.
It happened when I updated the tile set. I had to shift one of the assets because it wasn’t lined up the way it was supposed to do. I accidentally saved it with my gray background and it acted weird, so I went back and saved it with a transparent background like it should be and that’s when it happened.
One thing that might have happened, is that the tileset image changed width when you changed it. If that causes the number of tile columns in the tileset to change, Tiled has to renumber the tiles and adjust the map accordingly.
Before Tiled does that, it will ask you with a popup, which notes how many columns the tileset had before and how many it has now, and asks you whether you want the tile references to be adjusted. If you answered wrongly here by accident, then you’d generally notice that everything gets messed up and you can then undo the action.
Of course, when you closed Tiled then undo is no longer available. In that case, you can try to reverse the adjustment by exchanging the tileset image accordingly from one column count to another, and confirming the adjustment when it is the reverse of the wrongly applied adjustment.
In any case, if this caused the map to break then the information should still all be there, so you should make a backup and play around with trying to get it to be unbroken.
I don’t remember seeing a popup, but it’s not impossible that I missed it. I’ll keep trying to fix it, but If you don’t know how, then the chances of me figuring it out is pretty slim. My friend and I have been trying to troubleshoot it for hours and he’s better at this sort of stuff than I am. He said the select same tile tool shows the original tiles underneath and not the ones scratched over it, so maybe there’s hope.
Probably just going to have to bite the bullet and redraw the map, to be honest. Chalk this up to a learning experience and move forward. And be sure to have a few separate backups as I go.
That being said, Thank you so much for taking the time to try and help. I really love Tiled, it’s an awesome tool and I have no illusions that this was anything but my fault. Not sure what I did wrong, but I’m sure I’m the one who did it.