Doom was released exactly 30 years ago and to celebrate this anniversary John Romero designed a successor to to his previous WAD named SIGIL: the sixth episode of Doom named SIGIL II. You can download SIGIL II for free on his website: Romero.com SIGIL.
If you fancy a big box or want to play with the THORR Soundtracks you can order a copy as well. I bought the version with the THORR soundtracks and think it suits SIGIL II very well. If you liked the first version with Buckethead you'll like this one too .
Playing SIGIL
SIGIL II's maps are too complex for the original DOS Doom version. Though you do need the original Doom IWAD you can't play it on the original-original Doom. You'll need a modern source-port to play it. I've used ZDoom/GZDoom which you can find on zdoom.org. Copy both the original Ultimate Doom IWAD (DOOM.WAD) and the SIGIL_II.WAD into the GZDoom folder. You can launch SIGIL_II.WAD by dragging it onto the GZDoom executable. If you have the MP3 version you can drag the SIGIL_II_MP3_V1_0.WAD file- it includes both the music and the new levels.In-game I went to Options > Set Video Mode and configured the Doom Software Renderer. Default is Hardware Accelerated but I don't fancy the texture filtering that makes everything just a tad too blurry. It's a personal thing . Of course you can tune settings the way you like since GZDoom offers a lot of configuration options.