DERM Tool (Online)
Select Any Patch Date To Downgrade to.
What’s the difference between “Run in DERM” & “Download Batch File”?
“Run in DERM“: Prompts the downgrade automatically and directly through DERM Tool (This method is fast and recommended)
“Download Batch File“: Generates a batch script for your Windows system with all the commands lines you need to downgrade to the selected version. But you will also need to change the login, password and game directory then save the file.
Finally, you download the latest official Steam library DepotDownloader, extract it in a folder with the batch file we just modified then run the batch file (Watch this Youtube tutorial)