ZDoom is a family of enhanced ports of the Doom engine for running on modern operating systems.
It runs on Windows, Linux, and OS X, and adds new features not found in the games as originally
published by id Software.
For versions of Ubuntu between 14.04 LTS (Trusty Tahr) and 15.10 (Wily Werewolf), as well as Ubuntu flavours that don’t include snap by default, snap can be installed from the Ubuntu Software Centre by searching for snapd.
Alternatively, snapd can be installed from the command line:
sudo apt update
sudo apt install snapd
Either log out and back in again, or restart your system, to ensure snap’s paths are updated correctly.
To install GZDoom, simply use the following command: