Tits. May I say tits? How about penis? Blowjob? Lesbian porn? You see, without these rather colourful words, I fear I won't be able to convey the appropriate tone here. 90 minutes into Duke Nukem Forever and I've ripped the eyeball out the socket of a twenty-foot alien, pissed in countless urinals, scrawled a penis in a child's book, talked dirty to myself in the mirror and been fellated by twin blondes in tartan skirts with fun-bags the size of footballs. To curb the vulgarity of my language would mask what kind of an experience the game has to offer. It's rude, ridiculous and radically different to anything the FPS genre has seen since, well, Duke Nukem 3D.

This is a double-edged sword the size of which the FPS genre has likely never seen before. A large percentage of today's Call of Duty crowd just aren't going to 'get' Duke Nukem Forever. I was lucky enough to play the game in Las Vegas, surrounded by neon lights, poles and women (presumably strippers) with huge silicon-filled norks serving me drinks. Not only this, I know Duke's history; the intricacies of the 12-year development process and that the game has been an industry joke for most of that time. The game is fully aware of all this, too, of course; you have to admire Duke's habit of smashing down the fourth wall.

You may have had a chuckle at some of these things yourself after watching the trailer that recently hit the interwebs. The game itself jabs at your humour glands at every opportunity, reminding you that immaturity is, in fact, tremendously funny.

I'd talk about the opening 15 minutes of the game, and the huge penis (with veins and hairs) I drew on a white board to the elated cries of "that's genius!" from my EDF team mates, but this has been spoken about before in our last preview. Instead I'll talk about the new stuff; the first four or five levels of the game and the myriad of entertaining moments littered within them. After putting down his Duke-branded control pad (the first fifteen minutes of the game are in fact a game within the game), our narcissistic hero sets off on a stroll about the penthouse of his casino; Lady Killer.

It's here, without your guns or aliens to riddle with bullets, that you realise just how much work has gone into creating distractions from the main story. Walking into an employee lounge, you can pick up a bag of popcorn, cook it in the microwave and then eat it. You can urinate in any toilet you come across, drink any beer you happen to find, and play any slot machine that grabs the attention of your wallet. Perhaps the most interesting of these activities finds Duke pumping iron in the gym. After curling a few weights, the big man complains that they aren't heavy enough for his needs. The game doesn't tell you what to do, but intelligent players will start looking to add to the bar, eventually giving Duke a workout to be proud of. Taking the time to seek out these little events is more than just an entertaining distraction; it permanently increases your maximum health.

After faffing about in the corridors of the casino for some time, exploring every nook and cranny of the demo, I eventually started to pursue the story proper. On a satellite link with the President in his 'Duke Cave', our hero learns that the leader of the free world has made a deal with the alien invaders, and Duke is asked not to get involved. Not being the kind of guy that does what he's told, Duke decides stick his nose in regardless. It transpires that the aliens are looking to kidnap all the women (or babes, as Duke would call them) from Las Vegas, which pisses our womanising protagonist off even more. Despite what anybody thinks about Mr Nukem's views on women, he's willing to risk life and limb to save them.

It isn't long before you're furnished with guns and presented with hideous aliens to shoot. You'll do far more than just bloody up extra-terrestrial scumbags over the course of the game, however. During the first five levels, a Gearbox representative refused to let me do the same thing for more than a few minutes. After dispatching of a few rooms full of enemies, the game had me guiding an RC car through an obstacle course to retrieve an energy cell. Shortly after I was manning a turret and shooting down a mothership as the sky was transformed into a shooting gallery. After that I was stopping an out of control elevator from killing its buxom passenger. Then I was shrunk to the size of an action figure, taking the wheel of the aforementioned RC car and tearing up the casino on four wheels. My final moments with the game were squaring up against a colossal boss, and while I don't want to ruin what happens, I'm happy to report that testicles are involved. If variety is the spice of life, DNF is a spicy dish indeed.

Perhaps understandably, Duke Nukem Forever looks more than a little dated. This has been in development for twelve years, after all, with assets swapping hands left, right and centre. 'Dated' is putting it mildly, to be perfectly honest. The game looks unsightly for the most part, with polygon-starved models and poor textures. That said, the scrappy aesthetic works with what the game is trying to achieve. Duke Nukem Forever isn't attempting to compete with the likes of Crysis and Killzone; there's just no point. Instead, it revels in its 90's level design, dated environments and slightly misshapen character models. It's all part of the charm. For some inexplicable reason, the second-rate graphics seem to work in the game's favour.

The frame-rate isn't something that I can forgive so easily, however. Even two or three enemies on screen at the same time sent the frame rate plummeting into single digits. At times the game became borderline unplayable. I suffered numerous deaths because I couldn't process what the hell was going on, with enemies flitting about the screen like players with a dodgy internet connection might on CoD or Halo. Let's not fret about this too much here, though. Randy Pitchford himself assured us that there was still a long list of problems that the team intends to fix. Release day isn't too far off now, however, so let's hope the frame rate is near the top of that list.

There's a lot to love about DNF, but much of it will be wasted on those who know no better than the glorious corridors of Call of Duty and its ilk. The irony, in-jokes and self-referential humour will fly over the top of many heads, just as it might in something like Bulletstorm. Duke Nukem is scrappy, crude and laughably dated, and while a generation of gamers will inevitably hate it, there's another that will lap up every last morsel. The day the review embargoes lift for DNF will be an interesting one. It seems to me that scores are going to differ dramatically, but whatever the number on Metacritic, this is a game people are going to be talking about. Or shouting, perhaps. Hopefully with lots of delicious profanity thrown in for good measure.

Duke Nukem Forever is due for release on Xbox 360, PlayStation 3 and PC on May 6.