You would think that after a distress call and the knowledge that previous platoons have been decimated, the marines of Aliens: Colonial Marines would be hesitant to enter the fray. But the group enters with all the "oorah" it can muster, and the body count promptly begins to rise. That's what you get for underestimating xenomorphs.
A new story trailer for the game abbreviates this progression, showing the marines shouting about the prior (completely wiped out) groups before everything starts going wrong. The trailer doesn't imply a happy end for anyone aboard the ship, seeing as any survivors will at least need years of therapy.
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