God, I loved this game. It was the obvious next step along the Doom FPS chain. It had everything, fast action, big guns, humor and one of the best level creators in a game (and of course lots of partial nudity, every one boys dream game).
Personally, I think the thing that set this game apart from all the other Doom clones was Duke himself. His catchphrases would always come at the best times to sic you up to face a boss (and this game had some great bosses), and multiplayers usually ended up with all players throwing abuse at each other via Duke.
In single player you had a great storyline to follow, that I won't ruin for anyone who hasn't played, and some great levels. I think the Duke Nukem was one of the first FPS's to have destroyable scenery (but don't quote me), the first time you came to a dead-end and fired off a rocket in desperation only to have the wall in front of you blow up was amazing. Unfortunately, this usually led to you using all your big ammo on every wall you could find in the hope of finding more hidden areas, leaving you heavily out gunned when you met that levels boss. Talking about hidden things, there were plenty of those too, usually consisting of a scantily clad young
lady on a poster or in a hologram, good times for a young lad.
Although the single player mode was loads of fun it was the multiplayer that this game was made for. With the ability to create your own worlds, it meant a never ending supply of new and interesting levels (I remember spending days designing a Wild West town and the floating man-made island from water world). The fact that it was so easy to get into really helped and it you did get stuck the help option was actually helpful, not like most of those help / troubleshoot guides of today. To get the basics to minutes, but the pride of showing off a level that had some more advanced aspects was almost as good as actually playing in them. The only time I ever had a problem was with my mirror-maze idea (mirrors don't reflect other mirrors well)
Anyway, a review of the game can't really provide the levels of enjoyment that you get from playing, especially from a novice writer like myself, so please do yourself a favor and go play this game.