Description:

Chocolate Doom is a game engine that aims to accurately reproduce the experience
of playing vanilla Doom. It is a conservative, historically accurate Doom source
port, which is compatible with the thousands of mods and levels that were made
before the Doom source code was released. Rather than flashy new graphics,
Chocolate Doom's main features are its accurate reproduction of the game as it
was played in the 1990s.

The following games can be played:
-Doom (including the shareware and registered versions, and the Ultimate Doom expansion pack)
-Doom II
-Final Doom (TNT:Evilution, and the Plutonia Experiment)
-Chex Quest

It is also possible to play these expansion packs and commercial games, each of which requires one of the above:
-The Master Levels for Doom II
-Hacx

And also various TCs and WAD files:
http://www.chocolate-doom.org/wiki/index.php/User_guide

Warning! Chocolate Doom needs to know where to find your IWAD file. To do this,
put the file into /usr/share/games/doom or read INSTALL file in docs for other
possibilities.