Experiments over, we decide not to bother with the man on the roof after all. He's suffered enough (and continues to, judging by the four other pods around us where he's being stalked and killed over and over, sometimes by throwing knife, which we hadn't seen before). Instead we descend to the ground again (descent, incidentally, is as fluid as ascent), and pick on a soldier minding his own business on the other side of the bustling courtyard that fronts the warehouse entranceway. As we move in close, equipping our assassin's middle-finger blade with d-pad-left, we're told to hit X to assassinate, driving the knife into our prey and then backing away as his body slowly catches up with the fact he's dead and topples. His relatively gentle fall masks Altair's role believably, and as the dead man's noticed and the other guards approach, there's no question we could easily be missed - as we are, as we slink up the stairs towards the objective.
As we approach Talal, the game is taken somewhat out of our control, as assassin and target argue about whether one or both is being stitched up. Altair - and we agree, his voice is a bit pants - certainly sounds convinced, and Talal is obviously not counting on his words to solve the problem, dispatching half a dozen guards to the warehouse floor for the demo's inevitable battle sequence. The good news here is that those fearing a Prince of Persia dichotomy of stylish platforming and stumbling combat can calm themselves, because Assassin's may not be Devil May Cry or God of War, but it's not a time-waster either; instead it's somewhere in-between, with an emphasis on timing rather than technical knowledge. Guards advance, you tag them with the left trigger to lock on, hold the right trigger to parry their blows, and use the X button, struck just as they initiate their attacks, to counter them with an executional response. Tricky at first, the slick killing animations soon begin to flow, and well-timed counters have the added benefit of restocking your health-bar, meaning that we went from awkwardness on the back foot to violent gains within a matter of moments.
But there's no time to enjoy that, because Talal makes a break for it over the rooftop, and must be pursued and assassinated. This is where the minutes we spent messing around on the roof and dancing over the heads of civilians pay off, as our fleetness of flying foot allows us to close the gap in record time, take a final step off a market stall and leap onto his back to sink the blade in. As Talal expires, killer and victim speak again, on a white background, seeding yet more doubt as to the nature of Altair's mission.
When they finally shut up, the demo moves onto its final phase: the escape. Getting away will form the back-end to each of the game's nine missions, according to Ubisoft. The soldiers who chase you just want to keep the peace, and if you break the line of sight they will assume you're gone for good, which is fine by them, so the real trick isn't escaping so much as evading. Hiding spots pepper the mini-map, and you soon come to recognise them on sight. The devs claim to have avoided the copy-and-paste design that blights some 'sandbox' games, but they're sensible enough to allow for a uniformity of mechanical elements such as these, and - in another useful touch - legislate against the traditional stealth problem of not being able to tell when the coast is clear by offering an alternate camera view that tracks the nearest guard. When the alert status drops sufficiently, a message along the left indicates you can move off again, and make your way the final few steps to the assassins' headquarters. The message, playfully, says, "Reinitialising..."
It's one of a number of things that point to the 'big reveal' that we're all waiting for, and which Ubisoft continues not discussing. The noises in our headset that signal optional camera alternatives are called "glitches" by the developer walking us through the demo, while little splashes of glimmering data read-outs pop up around enemies and other elements, reinforcing the impression that Altair's Third Crusade home is not so ancient after all. The best hint we've had up to now actually came from an actress, Kristen Bell, who said that the story is based on the idea "that your genes might be able to hold memory", while the X06 demo included a reference to "memories /01" on the game-over screen. Altair is not a time-traveller, we're told again, but they're clearly going somewhere with this, and we doubt it's just the Holy Land.
Whether or not the game's secrets live up to their hype is not something Ubisoft's likely to help us decide any time soon - in fact, we'd be surprised if they openly discuss what it's all about this side of the game's release on PS3 and Xbox 360 in November - but the developers we talk to at E3 are adamant that the game itself will be compensation enough. The level we've played is "fairly early on", though not the first, and the full game will require players to complete missions to access some of the abilities we're able to use - certain weapons, techniques like grabbing the side of a building as you fall, or tackling people in the crowd - although the initial move-set is still aiming to impress.
Indeed, if the full game successfully expands on the range of mechanical and exploratory options on offer here, we're all in for a bit of a treat. Not unlike Killzone 2 and the USA Today screenshot, then, Assassin's Creed wasn't done any favours by its E3 conference presentation, but a proper look dispels some of the doubts it planted. Return roflcopters to roflpads.