|That said, iD released the source code, so there are a number of DOOM ports out there. None of them can legally include the graphics, sounds, textures, music, maps, or any other art asset I've failed to mention. These ports require you to import those art assets from the original game.|
How do you get the original game? Well DOOM 1 and 2 are both on sale on Steam for $7.50.
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