Freedoom is a free game project that can be used to play Doom without the original proprietary game files. However, the single player campaigns ("Freedoom: Phase 1 and 2") are not compatible with Chocolate Doom. Instead, it's recommended that you download the FreeDM multiplayer spinoff project, which is vanilla compatible and works with Chocolate Doom.
- Download and extract Chocolate Doom.
- Download and extract FreeDM (not "Freedoom Phase 1+2"), and move freedm.wad file into the same folder as Chocolate Doom.
- Run Chocolate Doom.
However, FreeDM's levels are intended for multiplayer deathmatch which might seem boring if you have nobody to play against (they don't contain any monsters). If you don't like deathmatch, you might instead want to download a single player megaWAD so that you get some more interesting levels to play.
 Doom 2 Megawads
The idgames archive is a good place to find WADs to play with. Not all levels will work with Chocolate Doom - look for levels that are marked as "Vanilla compatible", will run with "Doom 1.9", or "no advanced engine required".
To run a megaWAD, use a command line like the following:
chocolate-doom -iwad freedm.wad -merge mm.wad
|Icarus: Alien Vanguard||icarus.zip|
|Memento Mori II||mm2.zip|
More Doom 2 megawads can be found in the levels/doom2/megawads/ directory of the /idgames archive.
 Doom 1 Megawads (for freedoom1.wad)
You can also play Doom 1 megaWADs. For these you'll need to download the Freedoom single player campaign and use freedoom1.wad as the IWAD. For example:
chocolate-doom -iwad freedoom1.wad -merge dtwid.wad
Note that freedoom1.wad will not work properly with Chocolate Doom unless you use a megaWAD to replace the levels. The levels in freedoom1.wad are incompatible with Chocolate Doom and you will probably find that the game will crash if you try to play them.
|2002: A Doom Odyssey||2002ado.zip|
|Doom the Way id Did||dtwid.zip|
More Doom 1 megawads can be found in the levels/doom/megawads/ directory of the /idgames archive.