We've updated launch options on the game to mitigate a bug in the most recent release of Radeon driver software on Windows. If you have a Radeon card and experience video issues, including missing models or screen artifacting, you can try launching the game in Direct3D mode.
You can change the launch mode by right-clicking the game in your library and going to properties, where launch options will be on the first screen opened.
Radeon graphics card bug
Source: Steam Community (opens in a new tab)