There are many ways in which the deeply flawed Duke Nukem Forever fails to live up to the legacy of its legendary predecessor, but perhaps the most baffling issue is that the developers somehow managed to completely misunderstand the fundamental nature of Duke Nukem 3D's shooter design.
DNF partly succeeds in being an "old school" shooter and, as such, has a lot of similarities to games like Doom, Painkiller, Serious Sam and Necrovision. That's all fine in and of itself, but this retro vibe has virtually nothing to do with the original game that started this particular shooter series. For while Duke Nukem 3D certainly qualifies as an old game by now, it was never particularly old school to begin with. Indeed, because of the ambitious ways in which DN3D experimented with truly realistic environments, advanced scripted events and interactivity, it's much more accurate to characterize Duke Nukem 3D as the Half-Life of its time; i.e. an unusually sophisticated, mechanically complex and forward-thinking first person action game. That DN3D also happened to have a juvenile main character - who constituted an anachronistic throwback to a bygone era even back in 1996 - was always somewhat misleading given the sheer complexity and, yes, maturity of the game's overall design.
Anyway, regardless of what the classic Duke Nukem shooter actually was or wasn't, DNF must still be judged on its own merits. And when viewed as the most jarringly old-fashioned FPS to be released in 2011, the game kinda works. Perhaps you need to be a complete arcade shooter junkie and rabid anti-CoD/Halo fanatic like me to appreciate this at all, but I find the basic gameplay of Duke Nukem Forever to be solid enough and reasonably entertaining. However, it should immediately be said that there are some real missteps along the way, some more unforgivable than others. As one might have been expected given the patchwork of partly overlapping development cycles the game has gone through, the pacing is all over the place and the graphics are strangely colorless and washed-out. One gets the sense that a lot of blur was smeared on top of the visuals simply to disguise the sometimes shockingly low polygon count on both character models and backgrounds. Another more specific but no less notable issue is that the otherwise bland Hive level features some of the most despicable misogynist filth ever seen in a mainstream video game (...let's just say that the fact that the abducted women on the alien ship are passive victims deprived of all human agency is only the beginning of all that DNF does so offensively wrong in that section).
In spite of these significant problems, I feel like the core shooter mechanics get the job done and that most of the arena-like firefights constitute passable action entertainment. Even the awkward mini-games generally manage to provide some much-needed variation, and the way in which messing around with objects in the world (everything from microwave ovens to flipper tables etc.) increases the player's maximum health is a simple but effective method to encourage exploration.
Still, most of DNF's novelty value undeniably comes from the fact that it's a release which strictly speaking shouldn't even exist; and includes all sorts weird design quirks which you're guaranteed not to see in any other shooter released this year. At its core this is a game which tries very hard to be a bland and unremarkable FPS, but never quite manages to stay cohesive or even coherent enough to deserve the stamp of normalcy it so desperately desires. It's a weird experience, for sure, and hard to recommend to anyone. Still, for me at least it's all curiously compelling, somehow...