Downpatch Guide

Playing on an older version of Risk of Rain 2 is easy and doesn't require downloading any sketchy programs or patches from random websites if you already own a legitimate copy of the game.

First, open the Steam console by pasting this command in your browser or run box (Windows + R):

steam://open/console

Enter the following command in the Steam console to download the old version via Steam:

download_depot 632360 632361 9058106608706845920

This downloads the Devotion update, the latest patch before the Seekers of the Storm (SotS) update. The download may take a bit to complete.
Once it's done, it'll say which directory it downloaded to, for example:

Downloading depot 632361 (1786 MB) ...
Depot download complete : "C:\Program Files (x86)\Steam\steamapps\content\app_632360\depot_632361" (1871 files, manifest 9058106608706845920)

Navigate to this directory (yours may be different). Launch the game via the executable (Risk of Rain 2.exe) if you want to keep the SotS patch downloaded, or copy the files over to your game directory if you want to be able to launch the downpatch through Steam.

Having trouble / questions? Check out the Downpatch FAQ.