Come to Mama Trophy in Aliens vs. Predator
Come to Mama
Liberate the Matriarch
How to unlock Come to Mama
This is story related and cannot be missed.
This trophy is obtained near the beginning of level 1. After you succeed in escaping you will be required to free all the other xenomorphs that are being held, complete the next objective which is to kill everyone that gets in your way. Follow on to the next couple of objective markers until you reach a room with two guards and control panel that you have to interactive with. Simply kill these two guards and press to interactive with the control panel, a short cut-scene will follow where you see the matriarch being freed. You will get the trophy once the cutscene has finished.