VFS Explorer

VFS Explorer is a powerful yet intuitive graphic tool for viewing and extracting assets from VFS archives, such as those used in Pathologic 1 and a few other games by Ice-Pick Lodge.

It is available in English and Russian. There are official builds for Windows and Linux, and it can theoretically be ran on any 64-bit OS with Python support.

Get it on Nexusmods.

If there are no builds for your OS, see instructions here to run VFS Explorer from source code. You will need Python 3 installed and added into path (the specific ways of achieving this vary between operating systems). Afterwards, if you don't have git installed, instead of the first step, go to the main page of the repository, click on the green "Code" button, then click "Download ZIP" and unpack the downloaded archive.

For an introduction to using VFS Explorer, there is a section covering it in the Extracting assets from Pathologic tutorial on Pathomodding wiki.