Duke Nukem 3D is the third game in the Duke Nukem series by 3D Realms (formerly known as Apogee). However, it represents a departure in tone as well as gameplay style, as the first two were sidescrolling platformers. Duke 3D opted to become a first person shooter instead, improving upon DOOM's realistic environments and weaponry and also bringing forth a grittier, over-the-top action movie style set in a somewhat dystopian future. Even Duke himself got an overall, now sporting shades and spouting plenty of profanity and action film one-liners to complement the new turn (including, most infamously, a couple of iconic lines from Evil Dead).
Being set on Earth rather than in space (and hell) also lends itself to some rather clever level designs. Rather than just a lot of metallic corridors and toxic waste pits, you now get to venture through some Earth-based environments like a prison, a Chinese restaurant, a bank, a subway tunnel (complete with moving trains) and even a theme park, all rendered with surprising realism for a 1996 game. Of course the game still utilizes secrets hidden via walls and hidden switches and door locks with color-coded keycards, so it doesn't stray too far from the Doom formula. But still, it was a rather refreshing twist for the genre to see a game where you'd actually have to dig through cabinets and search various distinct and realistic rooms to locate everything.
The Build engine also brought some new factors to the level design which went well beyond DOOM's. First was the fact that levels could actually dynamically shift mid-stage - when certain switches were triggered or explosives were used in certain areas, you could actually blow holes in walls to reveal new areas, buildings could collapse and terrain could radically shift. This is probably most evident in the Grand Canyon stage, where Duke would walk up to a sign labeled "San Andreas Fault" and watch the whole canyon before him collapse in a massive explosion, allowing you to proceed further into the level.
The engine also allowed the game to have room-over-room design (cleverly disguised via player-teleporting eggs as it didn't actually support such things) and even underwater segments. Very often in the game, you'll actually have to dive underwater and traverse tunnels full of monsters in order to proceed through the stage. They actually went above-and-beyond in implementing this feature too, enabling not only full 3D movement for Duke in these segments, but amplifying all of the sound effects whilst underwater and requiring Scuba gear to stay under for extended periods of time without having your health rapidly drain. Now that's a keen eye for detail.
The weapons in the game were another innovation that helped set it apart from its predecessors. There was the usual complement of the pistol, shotgun and machine gun, which were reworked for a bit more realism this time around - the pistol actually utilizes clips and has to reload every twelve shots, and its high fire rate makes it a fairly useful weapon against weaker enemies. The shotgun is a pump-action model that requires an on-screen pump animation after each shot (giving it a slow fire rate but considerable punch) and the machine gun is a triple-barreled monster that mows through weaker enemies with ease, but also quickly burns through its ammo pool. The rocket launcher is your typical high-damage weapon, being able to blow up most weaker enemies in a single shot but also proving dangerous to the player at close range (and able to blow open certain walls to reveal new areas, as mentioned).
The rest of Duke's arsenal, however, is quite unique, especially for the time. There were pipe-bombs, which could be thrown out with one press of the fire button and activated with a second press, making them sort of akin to an early version of Goldeneye's remote mines (and a fun way to set traps for stubborn enemies). Laser tripbombs also made an appearance both as stage hazards and as a secondary enemy trap. These could be attached to almost any surface, and once the laser beam they emitted was crossed, they would detonate, damaging anything nearby. The Freezethrower (pictured above) allowed enemies to be frozen and then shattered with a single kick or gunshot - not terribly useful, but fun. Then there was my personal favorite, the Shrinker, which causes enemies to shrink to a miniscule size and become nearly harmless. Walking up to a shrunken enemy will cause Duke to stomp on it, killing them instantly.
The expansion also added one new weapon, a variant on the Shrinker called the Expander. This does quite the opposite of its cousin - instead of causing an enemy to shrink, it causes them to literally expand to double their normal size and then explode messily, damaging anything else that happens to be nearby. Again, it's not all that useful owing to its low damage output and ammo capacity, but it is amusing.
The usual complement of DOOM-esque powerups are also here - ammo packs, Atomic Health (which allows your health level to exceed its normal maximum) and various pickups that allow you to survive hazardous environments (boots and scuba gear). However, unlike DOOM, some of these can actually be picked up and carried around, utlizing them if and when you need them. For instance, the First Aid kit can restore your health at any time at the press of the "M" key, while the Night Vision goggles can be used to light up dark areas. Steroids multiply a player's movement speed and melee damage (but their effect cannot be stopped early) and the Jetpack actually allows free-range movement throughout the entire stage (to the limit of its fuel supply). Another pretty clever innovation in Duke's favor.
The enemies are just as varied in design and tactics as your weapons are, of course. You've got your basic grunts in the lizard soldiers and pig cops (with uniforms that say "LARD"... har har), as well as variants on these armed with teleporters and flying cars that move quickly throughout the stage, respectively. The expansion also adds a second variant on the Pig Cop that drives an armored vehicle decked out with machine guns. They're very hardy and tough to take down, but they can be instantly destroyed if you manage to sneak up on one and activate the self-destruct switch on its back.
Other enemies include octobrains (flying three-eyed monsters that fire psionic shockwaves), Assault Commanders (lizardmen with machine guns), Sentry Drones (annoying little robots that fly up to you and explode, doing heavy damage) and most annoyingly of all, Protozoid Slimers. These little things hatch out of eggs, then slowly ooze toward Duke - if they manage to get up close to him, they'll climb up onto you and bite your face, not only blocking your view but steadily draining your health as long as they remain detached. Firing any weapon will detach and destroy them, but if you're out of ammo you're kind of screwed...
Each of the four episodes also concludes with a unique boss battle, and these guys are no joke. The first one up is the Battlelord, a terrifying gigantic lizard trooper sporting a minigun that also fires a constant barrage of explosive mortars in your direction. It's also the fastest monster in the game, so outrunning it isn't an option. Basically, your only chance is to keep moving, fire on it with everything at your disposal and hope it goes down before you do...
Of course, being a violent game with a lot of questionable content, Duke Nukem 3D was also privy to a lot of controversy. The game features plenty of profanity and over-the-top gore well beyond DOOM's, with explosions actually causing dead enemies to throw gibs and blood across the level. Enemies can also be crushed into pulp in closing doors, leaving behind entrails that stretch whenever that door opens or closes. There's also a rather notorious scene where Duke follows through on a threat made to the second episode's boss to "rip his head off and shit down his neck".
Perhaps even more prevalent were claims of sexist content. These weren't entirely unsubstantiated, however, as many levels prominently feature strippers and women captured by aliens and "cocooned" in a manner reminiscent of aliens. Interacting with them causes Duke to slip them a $100 bill (resulting in a bit of pixelated boobage) or beg Duke to kill them, respectively. However, despite claims to the contrary, the player is never rewarded for killing women (and is in fact actively punished by virtue of the game spawning in more enemies for the player to fight).
Other controversies turned out to be little more than rumors. For instance, one particular easter egg that caused a bit of an uproar was the appearance of a dead marine resembling the protagonist of DOOM; Duke even remarks "That's one DOOMed space marine!" upon finding him. For a time, it was rumored that ID Software tried to file a copyright infringement suit over this appearance, but this was later proven to be untrue (and unlikely to happen in the first place, given that the two companies partnered on some earlier releases like Commander Keen). Another unsubstantiated rumor involved the NFL filing suit against 3D Realms, claiming that the game showed footage of actual football plays on in-game monitors without permission. Once again, though, nothing ever came of that.
That silliness aside, Duke Nukem 3D was an amazing title for its time, providing not only technology well in advance of DOOM's, but a heavy dose of loud, gory, campy fun that's still a ton of fun to play today. Like DOOM, it also sports a large modding community thanks to its built-in tools and a fairly recent release of its source code, which has enabled a lot of clever modifications and tons of fan-made levels to be created, lending it tons of replayability. DOOM may have layed the groundwork for virtually every shooter to come, but when it comes to old school arcadey shooting action, I dare say Duke 3D is the king of the genre. It's just a pity that 3D Realms never managed to make another game that was anywhere near as good as this one...
Note: to play these, you will need the original DOS version of the game (available at GOG.com) and the eDuke32 source port).
Duke Nukem Forever 2013 - If you've been gaming for any length of time, you probably know all about Duke Nukem Forever, Duke 3D's sequel that spent a staggering 13 years in development only to finally be released by Gearbox as a lame, buggy game full of tedious busywork, lame puzzles and awful humor. Needless to say, it was a massive letdown for the handful of people that kept the faith all that time, much less anyone else looking for a quality experience. However, this fan mod attempts to recreate Duke Nukem Forever as it 'should have been', recreating numerous scenes and elements from early trailers and gameplay footage in the Duke Nukem 3D engine. While it's still a bit short, it's definitely a much more satisfying experience overall, and it even has some pretty clever elements that weren't though to be possible given the engine's limitations like a rideable motorcycle.
War of Attrition - Something of an "RPG mod" that adds in a ton of new features to Duke Nukem 3D's gameplay. Weapons can be leveled up to give them greater damage as well as other abilities like damage over time or the ability to stun enemies. New weapons like the shock cannon and flamethrower are added. Powerups have new abilities (the Holoduke actually attacks enemies now and the night vision goggles cause you to become invisible, for example), and there are even a couple of new ones like the damage amplifier and a screen-clearing nuke. Over 200 fan-made maps are included for high score missions and the game's campaign mode. There are even new enemies and much tougher variants on existing ones, ensuring that despite your massive increase in power, enemies can still very much keep pace with you. All things that in various ways make this mod a very fun and frantic experience. Honestly, this may just be the best mod I've played for any game, period. I can't recommend it enough.