Aliens vs Predator is a first-person shooter developed by Rebellion Developments and published by Sega. In the mission Pyramid for the marine, the player will face Dr. Weyland, the man responsible for the unleash of the xenomorph. After a fight against him, the player will have to escape the pyramid and reach a chopper.

1. Exit the elevator and go to the sentry gun to activate it. Take your sniper and start shooting at the large wave of aliens coming at you. Shoot at their head for an instant kill. When they get closer, go take the heavy machine gun near the sentry and shoot at the xenomorphs attacking you. You can also shoot at the explosive barrel on the bridge to kill many with one shot.
2. After the attack, get on the bridge. Three tough aliens will appear. Stay behind the sentry and shoot at them when they get too close. Then, cross the bridge and enter the pyramid.
3. You will finally meet Weyland but he will try to kill you. Just after the cutscene, grab some weapons on the ground and take cover to the left. Kill the two androids aiming at you. Gather ammo and take the left path, two more androids will attack you. At the center of the room, there is a heavy machine gun. Take it and kill the four remaining androids. There is a total of eight enemies in the room. Then, take back your weapon and head to the objective marker.
4. Follow the hallway. You will have to confront Weyland and kill him. If you have the assault rifle with four grenades, the grenades will be enough to kill him. He has a shotgun so do not stay too close to him. You can also use the shotgun and the second shot of the weapon to inflict great damage. Find a spot where you can heal if you are almost dead.
5. Go to the top of the stairs and grab the datapad. Weyland will attack you again. Shoot him in the dead to kill him. 
6. The pyramid will collapse. Run and follow the marker on your radar to reach the chopper. Cross the room where you killed all the androids and exit the pyramid to clear the marine's campaign.