WGRealms DEMON THRONE is an action packed fantasy style total conversion of DukeNukem 3D using Eduke32. You don't need Duke 3D for this; just download and play for FREE!
This mod captures the spirit of classic FPS and expands upon it brilliantly. It provides a better single player FPS experience than any other game I've played, and I've played a lot of them. The kicker is that this is not only free, but standalone. It makes me sad knowing that loads of people spend money on games like Duke Nukem Forever, but this is free and hardly anyone knows about it.
The gameplay is imaginative and mostly flawless, though the throwing hammer is a little clunky and sometimes gets stuck. That's the only criticism I can come up with other than weapon balance, for example the ice storm seems a little too powerful for how little it costs. Sometimes I like to make Jedrik more challenging to play by not using those easymode everything-dies spells.
If you're a fan of classic FPS (or any kind of fun) you absolutely positively must play this. It changed the way I view the FPS genre and now everything is a little disappointing in comparison.