The third tone, however, finishes off the chord in exactly the right way, and brings resolution to all of the dissonance. Leonard Bernstein famously put the tritone to great use in the song "Maria" from West Side Story: "Ma-" is the beginning tone, "-ri-" shakes things up with some disharmony, and "-a" resolves the melody, justifying the lead couple's forbidden love.
Now, using that theory to talk about Blizzard's StarCraft 2 trilogy is a little unfair. The second campaign, Heart of the Swarm, isn't anywhere near "distasteful." But it does introduce plenty of new elements to the series, spinning off the RTS classic into places that Wings of Liberty never dared to go. And like that second note of a tritone, it makes sure to leave plenty of ambiguity and promise out there, making sure we're all ready for the big finale in Legacy of the Void. Throughout the entirety of the Heart of the Swarm campaign, Blizzard almost never has you playing the standard, fifteen-year-old StarCraft game. Yes, all of the mechanics are there when they're needed, so there are times when you do have to grow your overlords and make sure you've got enough vespene gas. But more often than not, the zerg campaign plays with the idea of what StarCraft, and a real-time strategy game in general, can be.
In one early mission, for example (seen in a press preview), you start out simply controlling a little bug, sneaking past powerful Protoss units and hiding in steam vents. That bug infects larger creatures and starts collecting biomass, and you can evolve up into a brood queen, with a few zerglings and roaches for escort. Evolve that queen further by collecting more biomass, and you can spawn more units on yourself, taking over an entire Protoss ship without ever mining a single crystal.
Other missions have further innovative takes on the RTS genre. In one, you're tasked with fighting a series of what are essentially World of Warcraft-style raid bosses while controlling one hero unit, and the whole thing feels strangely (in an exciting way) like a single-player League of Legends game. The clock is often used, and used well, as a motivator: Build enough troops to assault that building before time runs out, or race quickly to take out this unit before this point in the battle.
Putting the Zerg in the middle of such an experimental campaign is a very smart move. The species' basis on invasion, infestation, and evolution works very well in a setting where the rules (and the units) are always changing. As usual, Blizzard's cinematic sequences are brilliantly executed, and even in the mid-mission cutscenes, the various characters of the Zerg team shine through. Who knew a sociopathic, hivemind race could have so many charming and unique (if a little bloodthirsty) personalities?
The central story, however, belongs to Kerrigan, the Queen of Blades herself, and while Blizzard suggests that this is a love story (I'd like to coin "Kerrigaynor" as the correct term for the Kerrigan-Raynor pairing), it's really a revenge tale. Kerrigan's been wronged, by nearly everyone in the long history of StarCraft lore, and Heart of the Swarm is about her getting hers.
Unfortunately, while Kerrigan does have her moments, the story is overshadowed even at the meant-to-be-epic ending by the teasers and tendrils of the tale to be told in StarCraft 2's final chapter, Legacy of the Void. Blizzard spends a little too much time setting up its dominoes here to really give Kerrigan her full spotlight, and the story suffers for it. It's satisfying, but Blizzard doesn't attempt to hide the fact that it's got bigger plans coming.
The one weird misstep in the game's pacing are the "Evolution Missions," which are little interactive asides that give you the chance to play out two different versions of Zerg units, and then choose which one to add to your arsenal. The missions are well-designed, and genetic manipulator Abathur is probably the most interesting character of the Zerg cast, but they're clearly tutorials, and Blizzard seems to unlock them at strange times, like when you're right in the middle of the story's last few missions.
Finally, Heart of the Swarm adds an interface for user-made content called Arcade, which is a whole library of player-created (and a few official) mods and games using the extensive Map Editor. The new interface is very solid, and should help you browse through and stumble upon finds like the fan-made Starcraft Universe game (think "World of StarCraft"), as well as popular mini-games like Night of the Dead and Barcraft. The Arcade has a lot of potential for sure, and if someone makes a new Defense of the Ancients, that's where it'll be.
(Note: The new Arcade interface was added to the game last year with patch 1.5.0, but Blizzard has marketed it as a Heart of the Swarm feature. So it's not entirely new, and it doesn't require Heart of the Swarm to use, but we mention it here just because there is so much extra content in there to play through.)
Heart of the Swarm is an excellent expansion pack, and the campaign especially improves upon the somewhat limited variety that Wings of Liberty offered. It also shines a new light on the very race that made "zerg rushing" part of the lexicon of gaming, adding to the vast lore of this universe and introducing some new voices as well.
Heart of the Swarm isn't perfect. Blizzard spends time in the campaign teasing the story of Legacy of the Void when it could be doing Kerrigan's tale a bit more justice. Still, the expansion is well recommended to anyone who enjoyed Wings of Liberty.Heart of the Swarm shakes up the universe and moves a larger threat into place, getting us ready for the resolution in Legacy of the Void.
This review is based on a retail copy of StarCraft 2: Heart of the Swarm, provided by Blizzard.
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