Part 40

Proceed down the corridor until you have a clear shot at two explosive barrels.

Blow up the barrels with altfire hornets (secondary fire mode) as the security guard runs by.

Run to the guard and talk to him to make him follow you.

Lead the guard to the corner to the right of the corridor entrance and leave him there.

Wait with the assault rifle ready in case marines enter the room.

Crouch-walk (move slowly while staying low) carefully to the corridor entrance, firing hornets around the corner to hit nearby marines.

Continue slowly down the corridor, clearing out all marines.

If you haven't triggered section c2a5e, proceed down the corridor to do so.

Upon loading section c2a5e, turn around and return to the previous section to retrieve your security guard.

Return to section c2a5e and go to the back of the nearby truck. The previous back-and-forth should have eliminated the truck's turret; if not, shoot its leg with the pistol.

Jump into the truck and bash the crate for gauss gun ammo.

Move slowly past the truck until something ahead explodes.

Instruct your security guard to wait where he is, away from the danger ahead.

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

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

Equip your crossbow.

Crouch-walk very slowly to the corner until you can sneak-shoot the turret of the tank to the right without it firing.

Alternatively, use the crates against the back ledge to get on top of it and sneak-shoot the tank from there, aiming slightly above its turret. Patience allows destroying the turret with altfire hornets from this position.

After destroying the tank, kill the two nearby marines. You can sneak-shoot them around the corner or from the ledge with the hornet gun, or let them see you and shoot them with the gauss gun, watching out for their hand grenades.

Break nearby crates for health and armor.

If you missed the gauss gun ammo, return to the truck to pick it up.

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

Before entering the alley, locate the sniper nest high on a wall.

Hang back out of the sniper's range and throw a hand grenade at him after quicksaving (saving your game state).

Quickrestore (reload your save) and try again if you miss.

Enter the alley and wait for a bombing to occur; it will not harm you.

Find the only open door in the alley.

Equip the .357 pistol.

Crouch-walk carefully to the open door, looking left for a marine.

Sneak-shoot the marine; he will run towards you after one hit. Shoot him again instantly as he comes into view to prevent him from alerting his comrade.

Go through the door and carefully sneak to the corner, looking right for the next marine to sneak-shoot.

After both marines are down, bash the crates in their area for an armor battery.

Head up the stairs.

At the end of the upper floor area, you will find a security guard and a locked door leading to a supply area.

Get the guard to follow you, then stand near the door until he unlocks it.

If the guard was killed, return to the guard left at the bottom of the big ramp; he can also open this door.

In the supply room, use the light switch to turn on the lights.

Run along both rows of shelves to collect items.

Bash the crates in the back for extra goodies.

Go to the large window near the top of the stairs.

Crouch-jump onto the window's sill, then crouch-walk onto the narrow ledge beyond it.

Move along the ledge to a large light-green machine and jump onto it.

Jump from there to another light-green machine.

Take a running jump to the lowest ladder of the broken fire escape.

Climb the ladder to the fire escape, then climb its other ladder to reach the nearby roof.

(Optional extreme shortcut: Cross the roof, set two laser tripmines on the short wall as stepping stones, fall into the helipad area, use the crowbar to bash through the doors, and run to section c2a5f. This shortcut is impossible to take in the current version.)

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

Look down to see a marine on the floor below.

Equip your crossbow and use zoom mode to deliver a headshot (a shot that lands on the enemy's head, usually an instant kill) to the marine. (Note: It seems to be impossible to one-shot-kill these marines, so quickly two-shot them before they can alert others.)

Go down the large slanty beam that leads from the roof to the floor.

Turn around and move slowly toward a doorway with a light on a pillar past it.

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