Queen Mother

The four surviving squad members slogged through the Sycorax complex, fighting room to room as they made their way toward secured wing where they could access the Project Caliban data stored within the supercomputer Mother. To get to Mother, however, they had to defeat the brute shown below.

I was expecting it to be a challenging encounter, but the marines managed to sneak through the corridors using the aliens' own infestation to conceal their movements. They launched a surprise attack that cut down the beefy alien before it could make even a single attack!

Nathaniel's marine ran a bypass to open the door, allowing the squad to enter. They called up their two civilian allies -- a former criminal named Malone and a synthetic or "artificial person" named Alexander -- from elsewhere in the base. The boys' characters entered Mother's chamber along with Alexander.

Expecting to find an alien queen, they were shocked to learn that it was Mother who had released the xenomorphs from captivity, allowing them to run amok within the base and slaughter the human soldiers and scientists of Project Caliban. Calling herself the Queen Mother, she had decided that humans were unfit to control the xenomorphs. Then, in a heartbreaking scene, Mother reprogrammed Alexander and turned him against the heroes. Just as the boys were forced to destroy their friend (I had, in fact, built up Alexander as the primary NPC of the campaign and went out of my way to depict him as kind and helpful), a xenomorph hunting party returned to the base...