Along with lead world designer Leonard Boyarsky, who worked on Fallout, Metzen believes that it's been necessary to shed a little light in Diablo's relentlessly dark world, to leaven the bleakness, to give players hope and something to fight for. But their biggest challenge was to find a way to deliver story - including the backstory about the creation of Sanctuary, Diablo's world, by the rebel demons and angels who sired mankind - without slowing the game's voracious pace.
"Even if you don't stop and listen to all the quest text, the context of where you are and what you're doing strings together a little more directly in a way that I think is non-cumbersome," Metzen says. "That's a concern we've heard from Diablo players for years and years: 'Don't bore me with it, I'm really just interested in the slot-machine.' I think we've found a good compromise. We're not attempting to build Dragon Age here."
It's mostly, says Boyarsky, about keeping the word count down. But the elegant direction of the adventure and the discreet, optional delivery of backstory - mostly using dialogue and audio clips, so you can listen while you kill - are also hugely effective. That much is clear even from the beta's mini-adventure.
Your character arrives at New Tristram, a gold rush town thriving on the ruins of the village that was the setting of the original Diablo. Or it was thriving until a meteor drove straight into the old cathedral and raised a plague of undead commanded by the Skeleton King, an old foe from the first game.
Your journey takes you through some light skirmishes to a mission to rescue the series' aged sage, Deckard Cain, from the cathedral, at the urging of his adopted niece Leah. Once saved, Cain sends you off to find the Skeleton King's crown in a series of crypts so you may return to the cathedral to summon and then slay him. (This guy is going to die a lot while the beta is running.)
On the way, you're helped by a blacksmith - the first of the crafting artisans who will follow and supply your campaign against the Burning Hells - and, in the final battle through the cathedral, a Templar knight. The Templar is a 'follower', a sort of customisable henchman. These will join you at certain points to throw the story into relief with their comments as well as assist you in combat.
This first episode is simple stuff, but what's striking is how smoothly it flows, how much clearer your sense of place and purpose are than they were in the earlier games, how heightened the flavour and more varied the pacing. Like everything else about Diablo III, its narrative has an effortlessness about it that belies how carefully put together it is.
Little efficiency savings are everywhere. You now have three permanent utility items: a Stone of Recall to get you back to town (no longer viable as an escape skill); a Cauldron of Jordan that you can use to sell items wherever you are ("'My bag is full' is not an awesome reason to go back to town," says Wilson); and a Naphalem Cube which converts items into crafting material. There's less makework and more time to spend on new systems like that crafting, which balances the randomised loot by allowing you to predictably plug gaps in your equipment with decent-quality items.
But Boyarsky reveals that the team didn't get to include every novelty that it wanted to. "At one point, we were putting player choice in," he says. "You'd choose to finish quests in different ways, and with the speed of the gameplay and multiplayer and the flow of Diablo game, it just did not work... It just stopped the game in its tracks. It was a great idea, but it really didn't fit." The restraint is typical.
Diablo III is more game, cunningly disguised as less. Even after completing the beta twice over, it was painful tearing myself away from it; it's so disarmingly gratifying and deceptively sophisticated, and so, so much fun. This tantalising preview will only stoke your cravings. The game itself - now quite obviously, and vastly, better than its predecessors - can't come soon enough.