Humanity. That's what defines the final game in the Mass Effect trilogy. The struggle to save humanity - and everyone else in the galaxy - from the Reapers is its overarching theme. Playing as Shepard, newly reinstated to the Alliance after the events of Mass Effect 2, you're expected to be the big hero. So far, so predictable - but it's the battle for your own humanity that packs a punch.
Mass Effect 3's magic stems from your choices, the moral grey areas, and all-too-human failings of your companions. Make a bad choice, albeit in complex circumstances or under pressure, and the results might haunt you through the game's duration - and beyond.
One such decision left us reeling during our recent E3 gameplay demo. Visiting a mid-invasion Earth for disciplinary hearings after the events of Mass Effect 2 - we know, it's bureaucracy gone mad - we spot a child hiding in an air vent. Should Shepard tempt the urchin out from his hiding place? Or risk leaving him there to get killed? Encouraging the child out salves your conscience, but maybe it's a selfish act and he was safer in hiding.
So, imagine how we felt - how you'll feel - when the rescued child is loaded onto an escape shuttle that struggles to take off... before being blown to pieces. Damn.
It's a cheap shot deliberately included to yank our collective emotional chains, but it works. We recommend you have your 'No, I've just got something in my eye...' excuses at the ready. Mass Effect is superb at tweaking your emotions in a way that, for instance, the black and white morality of inFamous is not.
It's in combat we see the biggest changes. Gun in hand, Shepard now feels lethal. He moves with a speed and slickness you expect from the best pure action games; diving to cover, vaulting obstacles and slamming his new Omni-blade through enemies who stray too close.
Weaponry is more varied, and packs a bigger punch. BioWare are sharing sound tech with Battlefield 3 devs DICE, and the result is an arsenal that roars at the squeeze of a trigger. Weapons can be customised with up to five mods per gun, allowing you to tune them to your play style - recoil reduction, increased magazine size, scopes - whatever works best for you. They're the kind of goodies we've grown to expect, post-Modern Warfare.
To keep things balanced, enemies now have extra smarts. They flank, coordinate tactically and mix up their attacks to elevate fights from straight-up shooting gallery affairs. There are more at any given point and - for reasons BioWare are keeping secret - Shepard is now fighting both the Reapers and Cerberus, which means more than double the number of enemy types to kill.
The Reaper grunts are abominations made from races enslaved by the Collectors in Mass Effect 2 - part human, part Krogan, part Turian, part whatever - while Cerberus bring mechs and heavily armoured shock troops. As part of the more aggressive combat, Shepard can shoot the pilot out of a mech by blasting the glass and scoring a headshot, or pick off individual bits of machinery. BioWare are promising dismemberment of the Reaper abominations too, but we're yet to see this in action.
Back on the Normandy there are further improvements. The crew has been sharpened up, with Ashley and Kaiden - both survivors from the original - getting the most significant makeovers. The galaxy map now lets you select cities or areas on the surfaces of larger planets.
Don't fear an unwieldy ramble, though - in a previous interview series producer Casey Hudson explained the structure as focused but layered: the more you explore the storylines and side-plots, the deeper you dig into the mythology. You can opt for the bare-bones shooter experience, ignoring the exploration, but just because you can avoid it, doesn't mean it's not vital.
Fail to explore Mass Effect 3's galaxy of people, situations and fine details, and you'll fail to experience its near-unmatched humanity, fallibility and personality - the beating heart of this amazing series. And before you ask, yes, we're stopping at nothing to peer under Tali's mask.
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