itch.io

Just to be sure, I checked on the permissions of the files unzipped straight into my home directory:

jonathan@Odin:~$ ls -l Autonauts.*
-rw-rw-r-- 1 jonathan jonathan 31722796 Jul 23 09:24 Autonauts.x86
-rw-rw-r-- 1 jonathan jonathan 31348864 Jul 23 09:24 Autonauts.x86_64

You see that the owner and group (me, since I unzipped the files) have only read/write permissions (rw-); others have only read access(r--).  To run the files, I have to set the execute permission, which I do with

jonathan@Odin:~$ chmod u+x Autonauts.*

u+x means 'add the execute permission for the user (owner)'. Then the listing shows:

jonathan@Odin:~$ ls -l Autonauts.*
-rwxrw-r-- 1 jonathan jonathan 31722796 Jul 23 09:24 Autonauts.x86

If I was going to install the files somewhere where any user of this machine (Odin) could run them, then I'd use

chmod a+x Autonauts.*

You could try shipping the files with the execute permissions set; I don't know if that might trigger some security problems in some machines.  Most Linux users would be OK using chmod, as I have above.

More on chmod and permissions at https://en.wikipedia.org/wiki/Chmod#Symbolic_modes

Cheers

Jonathan