Two years on, Batman: Arkham City remains one of the most critically acclaimed video games of all time, and its British developer one of the industry's most respected studios.
So when given our first glimpse at the third and final entry in the trilogy, Batman: Arkham Knight, one question naturally preceded others: how inventive can Rocksteady be with its third iteration of the same idea?
As first impressions go, Arkham Knight couldn't have wowed us more. Our first look at the game - which was played on a development PC using an Xbox controller - begins with an astonishing, swooping view of Gotham City; swarms of immensely detailed high-rise buildings stretch out to the horizon, while thousands of light-sources create an eerie atmosphere by casting a shadow across the entire metropolis.
Down on the streets, the glare of enough neon signs to rival Time Square, and the dancing flames of a leftover riot, ripple hypnotically on the rain-slicked roads. The developer has previously claimed characters are comprised of more polygons than the entirely of Arkham Asylum's world, and up close it's easy to believe them - these models start to blur the line between in-game and CGI.
Arkham Knight is a truly incredible looking game - it's the stuff of futuristic Unreal Engine tech demos. And, as Rocksteady marketer Dax Gin explains, the visual fidelity is made possible by the decision to ditch last-gen console support entirely.
"By committing exclusively to next-gen hardware, what we've been able to do is build out the entirety of Gotham City," he explains, "a game world that is 20 times bigger than the world we created for Arkham Asylum and around five times bigger than Arkham City."
"But as with every game we've created, the clarity of your objective is important to us - Batman doesn't get lost in his own city."
Gotham City looks spectacular on its own, but is even more impressive when players view it suspended behind the the Dark Knight while he's free-falling off the top of a skyscraper; his cowl slicing through the rain as he expertly transitions into an elegant glide, sweeping across the Chinatown district.
Eventually, following the light emanating from a distant bat signal, and with the assistance of an upgraded Grapnel Boost, the Dark Knight arrives at a tall tower, where his old pal Commissioner Gordon is waiting. Gameplay seamlessly transitions to a cinematic - another impressive load-free flourish from Arkham Knight's modified Unreal Engine, which we'll all inevitably come to appreciate when entering and exiting interiors.
Gotham City has been evacuated and, according to Gordon, the only people left on the streets "are the sorts that enjoy the chaos". Just as the city was beginning to recover from the events of the previous game, a band of super villains - led by Scarecrow, who was a noticeably absent during Arkham City - have launched a WMD-style terror threat, with batches of deadly fear toxin ready to engulf all corners of the city.
So far Two-Face, Harley Quinn, Riddler and Scarecrow are confirmed to feature, with others set to be revealed in the future, and they've all joined forces to take down the Bat. This is all motivated by the shocking events at the end of Arkham City
"Arkham Knight is a truly incredible looking game - it's the stuff of futuristic tech demos."
"We felt that Joker, in a sense, was this random factor," game director Sefton Hill told our colleagues at Official PlayStation Magazine.
"This chaos, this disruptive figure that stopped the supervillains from coming together to take down Batman. But now that he's gone they can finally focus and see, 'right, our common enemy is Batman and we need to work together to take this guy down.'"
It's a structure that's not too dissimilar from last year's Warner Montreal-developed Arkham Origins. And as the bravado of Rocksteady's visual fireworks faded during the course of our demo, that feeling of familiarity became hard to ignore.
Mechanically, Arkham Knight is clearly a very similar game to its predecessor. Combat - one of the most universally praised aspects of the series - in particular has been largely, and perhaps wisely, untouched, offering the same rock-paper-scissors flow of its predecessors.
There are subtle new additions, of course; players can now weaken groups of foes with batarangs whilst gliding, steal weapons and throw enemies during counter moves. But otherwise it appears to be the same core brawling formula.
Similarly, the stealth sequences we were shown looked typical of the Arkham series, with Bats analysing and marking goons before selecting an appropriate tactical approach. This time, however, a new 'Fear Takedown' move allows Batman to knock out entire groups of enemies if he can get close enough without being seen. For these, formerly underused floor grates become very handy.
"Rocksteady insists the Batmobile will fit within the Arkham series' mantra of player choice"
By its own admission, Rocksteady believes the third - and supposedly final - instalment in its Arkham trilogy will be defined by one key new addition.
"Arkham Asylum was about atmosphere and in Arkham City we went open-world and explored what it's like to be the Caped Crusader, rather than just the world's greatest detective," Gin explains in an interview.
"I think in ten years' time, when people look back on Akrham Knight, it's going to be the presence of the Batmobile that's going to be seen as that stand-out feature. We could've tried to do everything, but what we've actually done is focus on delivering the most awesome Batmobile experience and how that affects every other aspect of gameplay."
With the press of a button, Batman places a holographic marker on the street, and what sounds like the combined thunderous roar of a dozen supercars announces the arrival of just one: the Batmobile. For the first time in the series, players will be able to tear through Gotham's conveniently wide streets behind the wheel of Bruce Wayne's legendary ride, which looks distinctly reminiscent of Christopher Nolan's Tumbler.
Like one of Respawn's fully-charged Titans, the Batmobile can be deployed at any time - and players can glide straight into the cockpit, (and, or course, eject out of it).
The act of getting behind the wheel and chasing down four-wheeled goons looks thrilling - if admittedly at odds with the sombre mood of Gotham - and in these moments gameplay takes on a Need for Speed vibe. That is, if Need for Speed had you blasting goons in an indestructible, heavily-weaponised Bugatti the size of a tank.
The Batmobile has the ability to boost and also lock-on to enemy vehicles with an immobilizing rocket launcher. It can also smash through almost anything; walls, street lamps and entire gas stations crumble before it.
The high-octane pursuits through Gotham's once-spooky streets accelerate gameplay to all-new action heights, but Rocksteady insists the Batmobile will fit within the Arkham series' mantra of player choice.
"The Batmobile is a tool that Batman uses in order to achieve certain goals," social manager Gaz Deaves tells us.
"He's always had his gadgets, and his ability to choose the right approach for every situation is one of the big aspects of being the Dark Knight.
"That's one of the ways in which we've tried to keep the balance with the Batmobile being more of a shock-and-awe approach and the existing grapple and glide mechanics offering a real distinction."
Essential or not, Rocksteady is clearly betting big on the Batmobile introducing positive disruption to an otherwise familiar formula.
A late sequence in our demo reveals the all-new Riddler Challenges, which now take the form of deadly races which have Batman boosting and drifting around bizarre, morphing tracks. Once such challenge gives players the ability to initiate changes in the course design with the press of a button, opening and closing doors and raising platforms at just the right movement, like WipEout on a pinball table.
Watching the batmobile pull off donuts and speed upside-down through a half-pipe is an undeniable thrill, but it's still difficult to shake the feeling that this sort of gameplay won't necessarily appeal to the entire Arkham series fanbase.
That said, there remain plenty of suggestions that we've not seen all Rocksteady has planned for its next-gen finale. The conclusion of our first-look reveals a brand new antagonist - the same 'Arkham Knight' referred to in the game's title - who appears looking like a militaristic Dark Knight and effortlessly knocks our hero to the ground, before pulling a pistol and announcing, "this ends tonight".
There's not much to know about the mysterious villain yet, other than that he's a wholly original character designed in conjunction with DC Comics. That in itself represents one of the most ambitious additions to Arkham Knight, and potentially bigger mysteries to come.