So this is basically what it looks like: 
This just started happening a few minutes ago. It happens when you get close enough to the terrain, once you zoom out it looks pretty much normal, but shadows are gone: 
This is the place it happens in: https://www.roblox.com/games/437253984/ALONE-Game
Changing the lighting settings does not affect this at all. Removing the post effects doesn’t change it either.
I’m using a GTX 1070, and this also happens for my friend who has a GT 740.
reminds me a lot of this
The shadow artifacts do look kind of similar yeah, but the pictures above are really close to (0, 0, 0) and it only happens for terrain and not parts 
I reverted the place to a version from yesterday - now everything is fine.
EDIT: It appears to be caused by some meshes, when they are added this weird lighting starts to appear.
Importing them into Studio again one by one fixed it.
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