So I finally achieved running that damned game on my Ubuntu Focal.
There is no system-wide solution as it needs libcurl3 and you will break your distro if you try to install it.
Instead, you must copy the three libraries and one symlink in your path/to/RiskOfRain/game/lib directory (google drive link provided here).
Then, edit the start.sh file and add at the line 19, just before ./"Risk_of_Rain":

export LD_LIBRARY_PATH=./lib

Run ./start.sh and enjoy.

Can confirm this is working. (For me at least.)

Thanks a lot Jaujon !
Works on Mint 20.1

best

Could you please re-upload the files, they are unfortunately no longer available.

Hi,

the problem is that RoR uses 32 bit libraries only as it's an ELF 32-bit LSB executable. Since most people are likely to run 64 bit now, the libraries need to be stored at a convient place such as the ./game/lib folder. But the files inside didn't work for me. After a bit of looking I ended up taking the deb files from https //packages ubuntu com for bionic (18.04LTS)

This works for Ubuntu 22.04.1 LTS 64-bit:
Create a bash file in your "~/GOG Games/Risk of Rain/libsetup.sh" with the content of the paste bin page with your favorite text editor.
https //pastebin com/Ma41bzkm # note I had to remove the dot and colons because I cannot post any links.

Then run it with
[code]
bash libsetup.sh
[/code]
or
[code]
chmod +x libsetup.sh && ./libsetup.sh
[/code]