Shepard is finally back on Earth. He has done the impossible and gathered the entire galaxy under one banner. The time to launch a counter-offensive against the Reapers is here. Every species need to give everything they had to mount the strongest possible counter-attack against a common, ancient, all-powerful enemy.

Countless strategies are considered carefully; all of the galaxy’s best military leaders gather to agonise over the best course of action. But before long, an inevitable answer is reached: to divide and conquer – to demand of the frontlines a necessary level of sacrifice so that a small team could safely initiate the Crucible.

The frontline is therefore built with the galaxy’s strongest soldiers. High-ranking humans, Asari, Krogans, Geth and even the remaining Batarians face their grim fates with gritted teeth and determination.
Fortified with powerful, heavy weapons and whatever remaining sources the galaxy has resources to ensure they hold the line. No matter what, the front cannot fall.

Will they return alive? No one can answer this question. But what is certain is that any sacrifice goes towards ensuring that the galaxy's final stand will be made.