zdoom (an enhanced port of the official DOOM source code)

ZDoom is a family of enhanced ports of the Doom engine to 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. It supports
Doom, Doom II, Heretic, Hexen, Strife, and more.

zdoom is only a game engine. To actually play the game, you'll need the
game data (IWAD file) from one or more of the supported games. These
include Doom, Ultimate Doom, Final Doom, FreeDoom, Heretic, Hexen,
and Strife. Place the .wad file(s) in /usr/share/games/doom.

If you don't own any of the supported games, you can install one or more
of these slackbuilds.org packages to get a playable game:

- freedoom
- doom_shareware_data
- heretic_shareware_data
- hexen_demo_data
- chexquest3

Optional compile time dependency: OpenAL, used for audio playback
(as an alternative to fmodapi, which is always built in). It will be
autodetected at build time. If you have OpenAL installed but want to
build zdoom without it, set OPENAL=no in the script's environment. There
have been reports that various mods work better with OpenAL, while others
crash or misbehave; YMMV.

Optional runtime dependencies: fluidsynth and fluid-soundfont, and/or
TiMidity++ and eawpats (used for MIDI playback). MIDI playback is still
possible when none of these are present, just select 'OPL Synth Emulation'
from the Options -> Sound Options -> MIDI Device menu within the game.
