Few would argue that Blizzard excels at creating expansion packs. Playing Diablo II without the Lord of Destruction add-on seems like a ridiculous proposition.
PREVIEW: We can recall fondly the high fantasy drama of Warcraft III: The Frozen Throne, and many consider World of Warcraft: The Burning Crusade to be the MMO's high watermark.
But perhaps none of these have had quite the same impact as StarCraft's Brood War expansion.
The add-on is frequently credited with facilitating the early rise of eSports, particularly in Korea, and its sweeping campaign was a gripping elaboration of the sci-fi universe and its lore. It remains one of the most important real-time strategy releases to date.
So it must be with some trepidation that gamers and Blizzard alike look toward to the release of StarCraft II's first expansion on the 12th of March. In the wake of such illustrious siblings, expectations for Heart of the Swarm are very high indeed.
Heart of the Swarm continues StarCraft's epic of sacrifice and betrayal, impending doom and flickering hope.
Sarah Kerrigan was a covert Ghost operative left to die by the ruthless leader of the Terrans, Arcturus Mengsk - only she didn't.
Instead, she was captured by the xenomorphic Zerg and assimilated into the Swarm.
Reborn as the Queen of Blades, Kerrigan led the Zerg on a rampage across the Korpulu sector, but her old flame, the idealistic rebel Jim Raynor, never stopped believing that her humanity remained suppressed deep within.
In StarCraft II: Wings of Liberty the tenacious Raynor and his ragged band of Terran allies defeat the Zerg, and Kerrigan appears to have been returned to her human form.
But even now, the Queen of Blades still lingers within Kerrigan, and her lust for vengeance has not abated:
THE DARK MIDDLE CHAPTER
In Heart of the Swarm, players control Kerrigan as she seeks to rebuild her power, and re-establish her dominion over the Zerg. The game has a much darker tone than Wings of Liberty.
It's a campaign that game director Dustin Browder hopes will give players a better sense of what it means to be a monster.
"It gives you a sense that Kerrigan has problems that Raynor just doesn't understand.
Kerrigan has much more serious concerns, she is in a much bigger universe than he is with much more serious issues, and she can't always get away clean. Raynor can always find a way to make it work, to still be the good guy.
"Kerrigan sometimes has to make the hard call. She's surrounded by these creatures that don't understand her, that are not sympathetic to her, and she doesn't always understand them either. That's what we're going for: this is the dark middle chapter of the trilogy."
Last week, members of the press were invited to play a handful of missions part way into the campaign. Kerrigan is reclaiming feral Zerg swarms on the icy planet of Kol'dir, and as she does so, she must also contend with small settlements of Protoss who are always a mere warpgate away from alerting the mighty Golden Armada to her presence.
In the campaign, Kerrigan will be a powerful hero unit that players will level up. As they do so, they'll be able to choose from pairs of abilities that will increase her effectiveness on the battlefield. Even this early in the game, Kerrigan is remarkably powerful, and it's something that radically changes the dynamics of campaign play when compared next to Wings of Liberty.
"She feels mighty - no question - and that's what we want," says Browder. "She can be a third or even half of your firepower, or if you want to kit her more passively, where she's buffing the swarm, you can kit her that way."
It's also a significant departure from an earlier build of the campaign that Gameplanet saw over a year and a half earlier. Then, Kerrigan had load-outs to choose from, or, as Browder calls it, "different flavours of Kerrigan."
"What would happen was that players would find their favourite version of Kerrigan and then never switch. What's the point in that? It didn't provide anyone with the challenge of new choices. Now, as you're going up you're adding more and more powers, adding to things you can do, and it means you're playing with more toys on the battlefield."
A SPLICE OF LIFE
Just as Kerrigan can mutate and evolve her powers, so too can her Swarm. As players advance through the early missions, they'll unlock new types of Zerg units, and these can be upgraded in two ways. Mutations present players with one of three options that will tweak the power of each unit type. For example, player might choose to mutate a unit for longer range, larger splash damage or more resilience.
Evolutions are more complex, and permanent. Abathur, the Zerg creature that oversees the evolution of Kerrigan's Swarm, will task her with small DNA-gathering missions that showcase the evolution options for each unit type. One mission might see Kerrigan with assimilating Zerg banelings that have evolved and learned how to jump up and down cliffs. Another might see her splicing baneling DNA with creatures that, upon death, split to create two smaller versions.
Unlike Wings of Liberty, however, structures will not be customisable. "We did discuss it some, and we tried a number of things: we had a Spore-Spine Crawler combo for a while, we had Spine Crawler with two tentacles on it - that was kind of fun. But we're really trying to get away from the Zerg defending a lot," says Browder. "We want the Zerg to be attacking and we're trying to organise our mechanics around that."
"We want you to be very aggressive, always attacking and sacrificing units - all for the greater good of the Swarm. That's been a challenge for us in the campaign, because you know most players start to feel - even for the Zerg - some empathy, and they don't want to lose troops. So that's what we're trying to push players towards."
THEY MOSTLY COME OUT AT NIGHT
True to Browder's vision, the majority of the missions shown to press coaxed aggressive play. Objectives are hidden deep behind enemy bases, and other timed events also demand a more offensive approach. At normal difficulty, what few raids the computer does carry out on Kerrigan's bases are quickly repelled or outright negated with only the most cursory of defences.
However, the final, and most memorable mission shown was altogether different. A Protoss spacecraft has slipped though Kerrigan's web, but the resurgent Queen of Blades has managed to smuggle a single, embryonic spawnling aboard.
The level begins almost as homage to Ridley Scott's Alien: the defenceless spawnling must avoid Protoss detection by hiding in shadows and crawl spaces, and by infesting research samples stowed aboard. Finally, the spawnling is strong enough to find a secluded area and mutate into a broodmother capable of spawning Zerg units of her own. Subsequently, she and her brood gut the husk of the ship.
It's a dynamically different passage of gameplay, but one that fits perfectly with the Zerg tone.
IN THE PIPE, FIVE BY FIVE
"I think because we chose to make the campaign so different to the multiplayer - we always told this half-truth, semi-lie that the campaign was a preparation for the multiplayer experience, and it never really was," says Browder. As the campaigns in StarCraft games diverge more and more from the multiplayer experience, Browder acknowledges that it has become even harder for those who enjoy the singleplayer to make the transition to the highly competitive online landscape.
"We certainly feel like we can do a better job teaching people to play the multiplayer game. We've had that feedback many times. I've been to trade shows, to BlizzCon, I've run into people who play the game, and a lot of them will say, 'I love the campaign but I don't - I don't play that scary [online] thing.' So I think we can certainly do better by them."
To aid players interested in making the transition to online, Heart of the Swarm will also include a huge suite of new training features. A revamped training mode will involve three missions that run in sequence. Each increases in pace, and each unlocks more technology while providing more objectives. Helpful tool tips will also tell players what to do at any time.
"We watch new players use it and they're always shocked," continues Browder. "'I need how many workers?' 'Four barracks is legit?'"
"I don't know if this will get you into Grandmaster, but it might at least get you into Bronze, right? That's what we're hoping for, for those players who are really struggling with that transition."
In addition to new levels of computer AI, Heart of the Swarm is also adding an AI Challenge mode that can be activated without any of the barriers that came with setting up a match versus the computer in Wings of Liberty. "[It] doesn't require you to go into a lobby, guess what your difficulty should be, try it, then pick a new map. It'll just find you a map that's on ladder today, automatically ramp you to your best difficulty and keep you at your best difficulty, and that will hopefully be a much more compelling versus AI experience."
For players already invested in StarCraft II multiplayer, Heart of the Swarm brings with it the welcome addition of unranked play. Browder describes a situation many players will know all too well: "You go home, you have a bad night - maybe you're a little sick, little tired, little drunk - and you lose five games. You ask yourself, 'Why did I even play tonight? I just wanted to-argh, now my ranking has tanked and I'm no closer to another achievement!'"
Closely tied to that is the levelling system already being tested in the online beta. The system is designed to reward players for winning, but also simply for playing. "If you play versus AI, you get experience, if you play certain maps you get experience, if you play 2v2, 1v1, 4v1, you get experience. It's not, as we felt it was with the achievement system in Wings of Liberty, a little too mean."
As players level up, they'll unlock new portraits, decals and skins. Browder acknowledges that the latter is a particularly difficult proposition. "We don't want to get so crazy that you can't recognise what these units are - this is still an eSport, and even if it's not an eSport, you're still playing competitively on ladder and trying to be serious about it, I don't want you to be confused by whether a Zergling has metabolic boost, or whether it's just an upgraded Zergling skin. We're really going to be tuning these over the next couple of weeks and making sure we've got it really tight."
Customisable Observer UIs will also be available come patch 2.0, but even Browder is unsure where such a feature will lead. "We started updating our obversver UI, but we thought, you know what would be a better idea? Instead of us doing that, let's give the tools to the community because there are so many casters out there that are such specialists at doing this right now, and maybe want to have their own take depending on how they're casting."
Replays are also being handled differently. Now, players will be able to watch replays together, and a previously announced feature, Start From Replay, will allow players to jump in at any point and take live control of a replay they're watching.
The most visceral highlight of the multiplayer component is the use of Domino Physics - the same creature physics used in Diablo III. Units will burst into scraps and flesh, then bounce off one another, and the environment. In the video shown, the physics were tuned right up for full effect, however, they're unlikely to be so intense.
"We won't be doing this much all the time because it gets really confusing and noisy," he explains. "You can turn this off, but our goal is to ride the line where it's really cool and not too obnoxious so that people will leave it on. We'll keep tuning that."
Together with what's already promising to be a robust singleplayer campaign, these changes to the multiplayer game do a great deal to suggest that Heart of the Swarm will be very warmly received by fans of the series, and perhaps even earn the it a place at the table with its hallowed predecessors.