Released in 2006, Human Head's Prey may not have set all hearts equally aflutter, but it was a first-person shooter with a few remarkable features.
It had portals before Portal. You could save your own life by going on a brief spiritual journey after getting shot in the face. And it had a Native American protagonist called Tommy who harnessed latent supernatural powers to punch body-harvesting aliens in the maw.
Perhaps strangely, then, Prey 2 dumps all that. You play a US Marshall called Killian Samuels and you're a bounty hunter on the planet Exodus, fighting your way through an openworld game inspired by Blade Runner and Mirror's Edge.
If this does not strike you as the most obvious course of action for a Prey sequel you are probably not alone, but developer Human Head does not agree. Prey, says studio founder Chris Rhinehart, was about taking players to a new place and employing new mechanics, using alien abduction as the entry point. These themes also form the basis of Prey 2.
One big change though is that while the first game's title could well have been a reference to Tommy for large sections of the action, the sequel aims to redress the balance. On Exodus the aliens are the prey, and you are the predator.
The game begins by tying Killian into the Prey narrative. You were on a plane that was harvested out of midair in full view of Tommy in the first game. You wake up inside an alien ship surrounded by plane wreckage, staring up at the Earth and stars through gaps in the hull.
You still have your sidearm - you're a US Marshall, after all - so unlike your fellow victims you can take the fight to the slavers who have ensnared you. This is done by diving into cover, popping out from behind objects in iron sights, blind-firing, sliding to other crates and doing all the other standard FPS things. Swap the Cthulhu tentacles and alien electronics for brown corridors and military fatigues and you could be playing anything.
But then you're smacked unconscious by a pair of aliens. You wake up some time later on Exodus, a world where one hemisphere always faces the sun. The section of the game we see is the Central City Bowery, just on the borderline between the light and dark faces of the planet, and we're picking up the action 31 days after Killian's revival.
The architecture is partly the retrofitted future of Ridley Scott, but it's equally reminiscent of Star Wars Episode II's Coruscant. Ships float through the air bearing neon ad hoardings, alien merchants flog fast food on platforms hundreds of metres above indiscernible gloom and everything is simultaneously bright and dark. Human Head calls it "alien noir".
Killian is a master of these surroundings. He prowls the streets using one of a range of gadgets to track down potential bounties, using a mixture of guns, gadgets and parkour to deliver whatever fate he's been paid to regard as justice.
Prey may have been a classic run-and-fire FPS in some respects - one of those games where your weapon is always on-screen and your first instinct is to pull the trigger - but Prey 2 aspires to be an action-adventure. It even boasts light RPG elements for handling upgrades and gadgets. The act of raising a weapon now has to be initiated and it has ramifications in the world, where aliens cower, flee or perhaps raise their own gun in reply.
When he does get in a fight Killian still has all the cover mechanics you saw earlier, now augmented by the ability to vault and climb across the environment. He uses the verticality as much to his advantage as the networks of walkways and plazas that form the concourses and communal areas of this crime-ridden neighbourhood.
For instance, if you're being attacked by aliens from above, you can springboard yourself off a crate and grab hold of a railing directly beneath them, then hang from it and pop up as though it were regular cover - a new variable in the usually unbalanced equation that pits FPS players against elevated adversaries.
Then, if you look up at a nearby ledge, Killian may raise his hand a little to show he can leap to that. Along with the unobtrusive inventory wheel, it's a nice visual indicator of something you can do rather than a heavy-handed menu or prompt. It reflects Human Head's desire to keep you in the gameworld rather than drown you in video game paraphernalia.
Combat also owes a lot to gadgets. These keep track of scanned enemies through walls, allow you to disarm turret gunners by hoisting them into the air on an anti-gravity field and let you fire rockets from your shoulder, amongst other things. They're activated independently of your main weapon, like the plasmids in BioShock 2, so combat remains fluid.
Not all of them are combat-related. There's also a hover gadget which lets you glide down to lower levels, Batman-style. (And "Batman-style" is usually a good phrase to have associated with your game, if nothing else.)
There are procedurally generated mini-missions all about the place - like an alien being beaten up by other aliens, who may give you some cash if you rescue him - and other varieties of sideshow. Some bounties come willingly with a bit of threatening, others have allies nearby who put up a fight, and some need to be taken alive with the helpful application of electric bolas.
Other missions will be a bit more complex. For example, on the way to tracking down a bounty he or she may get in touch via the ubiquitous communication system, plead innocence and offer a counter proposal - to go after your much dirtier employer instead. How you respond depends on your own morals.
Your behaviour towards the aliens you meet is noted by an explicit, Red Dead Redemption-style honour meter, although we don't see this in action. What we do see is that if you go too far you incur the wrath of local security - flying bagel-shaped drones with searchlights and bad attitudes.
As with Grand Theft Auto and other openworld games with policing elements, persistent offences garner more attention. There are also ways to lay low and reduce your profile.
So far, you could be forgiven for envisaging a cross between Mass Effect 2 and Assassin's Creed 2. But Prey 2 is not yet as polished as the former and it is hard to say whether it is as fluid and densely populated with content as the latter. Story details and more explanation of its structure will hopefully be forthcoming soon.
It's also difficult to be inspired by the locations at this stage. RAGE, which was on show the same day as Prey 2, has a lot of character and diverse influences, but the Bowery is slightly monotonous at this stage. Places like a casino and a strip club are prosaic, populated by funny aliens on slot machines and holographic pole dancers.
When asked about this Human Head says it wants to create a recognisable visual language for the world first, before diversifying into more eccentric super-alien concepts, which is perhaps fair enough.
Where Prey 2 is genuinely eye-catching and exciting to behold, however, is when all the toys are brought together for key missions. The one we get to see involves hunting down a chap called Dra'Gar. Your client tells you he must be brought in alive and that an informant named Krux may know where he is.
Krux is a guy you will encounter throughout the game. When you climb up to his perch high in the starry sky, he offers to tell you where Dra'Gar is for 2000 credits. You only have 1643 though, so you can either go away and get more by doing other missions or try something else.
The "something else" in this case involves threatening him - by shooting his bodyguard backwards off the platform.
"Your reputation precedes you," Dra'Gar notes. "They said you were stupid. I will give you the information, but you can expect me to call in a favour down the line." Apparently this means he'll become a mission-giver at some point, although it's not clear if he would have done so anyway.
Dra'Gar is in a nightclub. You grab a nearby thug as a human shield and make your way toward him, but he has legions of bodyguards who quickly reduce your barrier to pulp. Dra'Gar, meanwhile, has some sort of teleportation device and beats a hasty retreat. The chase is on.
You throw grenades, but this only results in a charmingly warm explosion that takes out a few goons. You toss some more electric bolas, but these only bring him to the ground long enough for him to teleport ahead. You fire rockets but Dra'Gar dodges through walls, so you pursue using parkour moves to duck and dive through holes and under tables. It's very stylish to watch, although we don't get to sample how it works under your control.
In a dark bar, you draw on your night-vision gadget to carve through more of Dra'Gar's bewildered entourage. In the next alley he sets a chaingunner on you, who you lift up with anti-grav and punish with a railgun.
He then teleports over some railway lines as a pair of trains go past in opposite directions, and like a modern-day Frogger you leap onto one going one way then leap to the next and ride it back to the area into which he fled.
"There's still a lot to prove, and in the eyes of fans who are upset by the absence of portals and the decision not to bother with multiplayer, perhaps a lot to answer for."
Dra'Gar's teleporter wasn't made for this much use, though, and at this point it goes on the fritz. You calmly walk up to him and he offers you a bribe. It's more money than you would earn turning him in, but you do so anyway, placing him in a restraining field that then prompts you either to interrogate him or send him through a portal to the client.
Having taken the latter option, you're rewarded by a message from a guy called S'Dyi, who says he is Dra'Gar's brother and you're in trouble. In classic video game preview style our presentation ends as a stompy monster with three legs, a big skull head and tons of weapons hones into view to settle the score.
Human Head says that Prey 2 will be a largely linear story within an open game - similar, in terms of how much choice it gives you, to something like Red Dead. Apparently it will take around 15 hours to rush through, more if you soak up the world around you. Other diversions include a range of tracking devices to uncover and disable, which add exploratory depth and a bit of narrative colour like the radio messages in Crackdown 2.
There's still a lot to prove, and in the eyes of fans who are upset by the absence of portals and the decision not to bother with multiplayer, perhaps a lot to answer for. In many ways, however, Prey 2 is refreshing.
There is of course continuity - expect to bump into Tommy somewhere on Exodus, for example - but there is also bravery. Human Head is willing to risk alienating the clutch of people who remember its cult shooter with a new approach, because it believes sequels need a distinctive creative direction.
Whether this approach will pay off remains to be seen, but we certainly wouldn't mind if more sequels threw caution to the wind and tried something new. If you weren't already tracking Prey 2's progress, we recommend you start now.