Real (REAL.ZIP)

Joe Zona is probably best known for his "Golden Triangle" level in Twilight Warrior, but the resources that made Black Shadow's jungle levels so engrossing had their origins in Zona's earlier release, the Real Doom II conversion, published a year earlier in 1998. Real is a short episode, fielding six real maps with an eye-candy finale, that tells the story of a marine sent in to clear out a Brazilian UAC base that tempted fate and is now overrun by Hellspawn. Your goal is to clear the nasties and find the base generator in order to rig it to explode in Hollywood fashion so that you can put an end to UAC's gateway experiments on earth.

Twilight Warrior (TWILIGHT.WAD)

For awhile, Doom was perhaps the most realistic FPS kicking around, as laughable as that sounds. It was, though, and it's only natural that authors would try to manipulate the core aspects of Doom's gameplay in order to facilitate an experience even closer to conceptions of what a realistic first person shooter experience would  be. Two wild and crazy guys - "Ziggy" and "Sidearm Joe" - made a series of levels called Hostage Rescue that tried to emulate this experience, but their efforts came to a head in 1998 with the release of Twilight Warrior, published as Black Shadow Software with the aid of some other authors, some now quite famous in the Doom community. It's a ten-map episode for Doom II, originally designed to be played in what is  now an ancient version of the Legacy engine. Nowadays, any modern port that supports mouselook, jumping and DeHackEd should be able to run it.