Part 40

In the winding corridor, use explosive barrels to eliminate approaching marines. Recruit a security guard and have him follow you.

Lead the guard to a corner and leave him.

Crouch-walk to the corridor entrance, using altfire hornets to clear out any marines around the corner. Proceed slowly until all marines are dead. Ensure you trigger section c2a5e.

Upon loading section c2a5e, immediately return to the previous section to retrieve your security guard.

Return to section c2a5e and go to the back of the truck. This should eliminate the turret. If not, shoot it with the pistol.

Enter the truck and bash the crate for gauss gun ammo.

Move past the truck slowly. Have your security guard wait before proceeding to the area ahead where something explodes.

Run up the large ramp, turn right, and run up the smaller ramp.

Hide near the wrecked door until a jet bombs alien grunts. Equip your crossbow.

Crouch-walk to the corner and sneak-shoot the turret of the tank to the right.

After destroying the tank's turret, kill the two nearby marines. You can sneak-shoot them or let them see you and use the gauss gun, watching out for grenades.

Break nearby crates for health and armor. If you missed the gauss gun ammo, return to the truck.

Go to the destroyed tank, turn right, and head to the start of a back alley.

Locate the sniper nest high on a wall before entering the alley. Save your game. Throw a hand grenade at the sniper. Quick-save and quick-restore if you miss.

Enter the alley and wait for a bombing to occur (it won't harm you).

Find the only open door in the alley. Equip the .357.

Crouch-walk to the open door and sneak-shoot the marine to the left. Shoot him again as he runs into view to prevent him from alerting his comrade.

Enter the room and sneak to the corner, then sneak-shoot the next marine to the right.

Bash the crates in their area for an armor battery.

Head up the stairs. Near the locked door at the end of the upper floor, get the security guard to follow you.

Stand near the door until the guard unlocks it. If the guard was killed, retrieve the guard from the bottom of the big ramp.

In the supply room, turn on the lights. Run along the shelves to pick up items. Bash the crates in the back for extra goodies.

Go to the big window near the top of the stairs. Crouch-jump onto the window sill, then crouch-walk onto the narrow ledge.

Move along the ledge to a large light-green machine, then jump to another light-green machine.

Take a running jump to the broken fire escape's lowest ladder. Climb it, then climb the other ladder to reach the nearby roof.

Cross the roof to its other side and slowly crouch-walk to the jagged edge.

Look down and use your crossbow's zoom mode to headshot the marine below.

Get on the large slanty beam leading to the floor. Crouch-walk down until you can see another marine through a doorway to the left. Use zoom mode to headshot him. (Note: It may take two shots to kill these marines before they alert others).

Go to the bottom of the slanty beam, turn around, and move slowly toward a doorway with a light on a pillar.

The final marine is past the doorway and to the right. Sneak up to sneak-shoot him with the .357.