Thanks for taking a look at Eldritch Academy, I hope you like it!
For this game, the "PC" build should work with Linux, from what I'm told. (The Ren'Py distribution builder says that it should work on both Windows and Linux. When it packages for just one or the other, it uses "Windows" or "Linux" as the build name.) That said, I have no Linux devices to test on, so it could be helpful to hear if this is true.
Yes, it does work. The presence of a shell script launcher ("Eldritch Academy.sh") and the 32 & 64 bit linux library folders in lib/ already indicate that. I tried it on Debian 8 x64 Linux just now, and the game does work, as long as the user knows how to make it launch. ;)
Since you're distributing the game in a non-POSIX compliant way (.zip archives), POSIX permissions aren't preserved. So, to make the game work, you have to enter the game directory and make the game binary and its launcher script executable first (here, I'm doing that for both the 32-bit and 64-bit versions):
$ chmod +x ./Eldritch\ Academy.sh
$ chmod +x ./lib/linux-x86_64/Eldritch\ Academy
$ chmod +x ./lib/linux-i686/Eldritch\ Academy
After that, it can be launched like this from within the main game directory:
$ ./Eldritch\ Academy.sh
I just didn't pay enough attention at first, which is how I missed the fact that your game already supports Linux, my apologies for that!
I have no experience with the Ren'Py builder myself, but to make the game work on Linux out of the box, the builder would need to package the files in a POSIX-compliant .tar.gz, .tar.bz2, .tar.xz or similar archive and set the executable permissions for you.
But it's no big deal, as most Linux users are likely to figure such things out by themselves anyway.
So, I'm off to playread Eldritch Academy! :)
