A child dies.

It's bold, dangerous, and clearly indicative of Mass Effect 3's darker tone, but does BioWare really think it can sum up the narrative weight of an entire universe on the brink of utter eradication with the on-screen death of a single child?

This affecting casualty is a micro element of the bigger picture. This is Earth, and it's under attack by the Reapers. Shepard, previously accused of crying wolf over the imminent threat, is stripped of his rank and forced to stand trial for the events of Mass Effect 2's Arrival DLC. Watching the chic, Apple-tinged cityscape collapse under the weight of these invading monstrosities so gargantuan they dwarf the skyline is certainly one way for Shepard to say I told you so.

War of the Worlds? Think War of the Galaxy, with Shepard having to flee a quickly-crumbling Earth and head out into the galaxy to rouse the assorted races into a stable alliance. These blockbuster moments are sheer aesthetic spectacle, and if you've been grooming your own personal Shepard since 2008 each powerful explosion simply intensifies your yearning for the finished game.

Mass Effect 3 is the culmination of a trilogy, of course - it's the climax to almost everything that happened in the first two games. The bombast and spectacle are justified by the occasion, though the current focus on explosions as opposed to conversation might worry some long-time fans of the series. But how would a dialogue wheel possibly suffice with the Reapers decimating the entire galaxy?

Shepard is stronger and nimbler than before, smoothly darting in and out of cover in a way that suggests the crew of the Normandy have been brushing up on their third-person shooters during the downtime between games.

Combat has been beefed up in response to the extra agility. Gunfights twist and weave around environments as opposed to having Shepard bunker down at the nearest spot of cover for the entire duration of the encounter. Enemy AI is now meaner and more aggressive, making a noticeable effort to flush you out of your comfort zone at every opportunity.

The omni-tool has been upgraded to include a blade, which now turns Shepard's melee encounters into devastating instant kills with flashy camera angles. Like in Arkham Asylum or Uncharted 2, players can even make use of stealthy approaches to grab enemies from behind cover spots and do away with them silently.

Grenades return as proper items, too, and guns fire in powerful clumps of deep bass. Weapons can also be upgraded with attachments at various benches around the levels, and Shepard will need the extra oomph - between knocking back waves of Husks, spawned from the corpses of multiple races, Shepard also has Cerberus, who've been properly indoctrinated by the Reapers, to contend with.

BioWare is determined to show that it's bringing out the big guns to conclude the trilogy, and the E3 demo is even rounded off with a bombastic on-rails vehicle sequence which has Shepard squaring off against a Reaper.

Mass Effect 3's more delicate moments will surely unfold over time, but right now it seems like BioWare is more than happy to show the world it's ready to go toe-to-toe with the best of the shooter genre.

Mass Effect 3 is scheduled to be released on March 9 2012 for 360, PS3, and PC.