Aliens vs Predator is a first-person shooter developed by Rebellion Developments and published by Sega. In the mission Ruins for the marine, the player will enter the ancient ruins of the predator civilization and will have to find Tequila and escort her to the lab. A predator will stand in the way and will have to be defeated.

1. Head straight into the cave. At some point, take the left path that goes up and turn left again. Cross the bridge to get on the other side and follow the path. Go down and get to the objective marker. Run to avoid the aliens.
2. When you get to the temple's entrance, go up the stairs and activate the switch to hack the door. During the hacking, stay behind a column and kill the few aliens attacking you. Stay in cover and let them come to you.
3. When the bypass is complete, enter the ruins. As soon as you are inside, run and get behind cover the column. Kill the two androids behind the rocks and go upstairs. Walk slowly and kill the four other androids on the second floor. Aim for the limbs and stay well in cover. The shotgun is a useful weapon in that situation.
4. Climb the rocks and get on the other side. Go down to regroup with the marines. Take the heavy machine gun and stand on the stairs. This weapon can automatically lock the enemies so stay high to have a good view and shoot at everything coming at you. The aliens will come from everywhere so be alert and keep an eye on your radar.
5. When the fight is over, regroup and follow your team. Keep the heavy machine gun if possible, you will find ammo later. Shoot at the aliens coming from the ruins and go up.
6. When you reach the ship, a dozen aliens will attack you. Shoot them with the heavy machine gun and switch to another weapon if you miss ammo. When they are allo down, go up the stairs and enter the temple to look for Tequila.
7. As soon as you enter, you will witness the murder of a marine by a predator. Follow the path with your partner and kill the multiple aliens on the way. The place is quite dark so keep your eyes open. Continue to follow your partner inside the ruins.
8. After you reach the top of the pyramid, your teammate will go on but will get captured and pulled through a hole. Go down the stairs and turn left to find a closed door. Use your device to hack into the system. Stay alert during the hacking and enter when complete.
9. In the next area, go down the stairs and head to the building. As you try to open the door, a predator will get you and throw you in the arena. You will have to defeat him in order to contine.
10. At first, the predator will stay on high ground and shoot at you with its laser. Try to spot him on your radar or look ar the red glow of his weapon. When you see him on a building, shoot at him with everything you have. When his blue life is depleted, the predator will go on the ground to attack you. Spot him and shoot at him before he attacks you. If he does, protect and counter attack to throw him on the ground. Shoot at him when he is down. If he is not dead, the blue life will replenish and you will have to repeat the operation until he dies.
11. Go back to the cabin and use the computer to find clues about Tequila. Leave the cabin and step inside the tunnels. Kill all the aliens one by one as you see them. At the end, you will find Tequila. Take her and exit the place. Go back to the cabin and go back to the arena where you killed the predator. Protect Tequila from the aliens and escort her to the exit. Let her open the door and leave the ruins.