1. Um, yeah -- you first.
2. After encountering a solitary head crab zombie on the left, zap your way into this building.
3. There's lots of objects - and targets - for your gravity gun in here. For a real thrill set this zombie on fire with one of the flammable canisters.
4. Tossing these saw blades at the zombies slices them in half!
5. To see more zombies split in half, crouch under this rotating blade to trigger these zombies to attack. Back up a ways and the two will walk right into their own demise.
6. Another zombie chopper is in here. Turn it on by crouching and then using the switch. Health packs are under the table behind me in this shot. Continue through the boarded-up doorway on the right.
7. Toss explosive barrels at the zombie in this alley, and light up the room on the right before entering (inset). You continue to hear the ramblings of a not-too-distant voice.
8. The source of the voice is around the next bend. Reminiscent of Charlton Heston's Omega Man, a determined survivor is seen on the balcony above.
9. Ignore the burning building for the moment. Instead, head right and take out the two zombies that crash through this doorway.
10. Inside are supplies and a sadistic little puzzle that reveals the trick to this area. Gas + spark = flame. Turn on the gas at (1) then ignite a spark by throwing the red switch at (2). The zombie inside the cage catches fire.
11. A bit farther up the lane is this scenario. Turn off the gas to stop the flames, then turn it on again. You'll see the shimmer of gas but it is safe to proceed into the alley and trigger a zombie attack. Backtrack to this position and throw the spark switch, setting your foes on fire.
12. Turn off the gas to venture into the alley again. This is currently a dead-end due to the electrified ladder.
13. Armed with your knowledge of gas and sparks, return to the burning building and turn off the gas here. Note the medkit.
14. Enter the building and clear out the first area by tossing a flammable barrel. Use your gravity gun to remove this barricade.
15. Ascend the stairs, taking out zombies along the way by making use of the flammable canisters and saw blades handily laying around.
16. This room has some particularly nasty dark head crabs. I ended up shooting them with the .357 because they continue to attack for quite a while even when on fire.
17. Most important is this switch. Throw it to turn off the power and de-electrify the ladder outside.
18. Backtrack downstairs. More dark head crabs are near the entrance, and here is another way out. Climb up to the indicated air vent. (Start by jumping on the railing to the left.) Use your crowbar to crash through and find some supplies.
19. Return to the ladder. Climb the ladder then ascend this fire escape.
20. Jump across to this ledge.
21. Crazy Survival Guy makes another appearance, shooting a dark head crab behind you.
22. Drop to the planks below and enter the window as indicated.
23. Before dropping below, toss a canister at the lurking zombie. Your 9mm is well-suited to clean up any remaining head crabs.
24. Use your crowbar to bust through some boards and arrive at this useful contraption. A well-timed pull of the lever will drop the old car onto approaching zombies.
25. This identical contraption is just ahead. Notice the lambda on the right. Drop the car, then quickly jump onto its hood before it begins to rise. Once it's elevated, you can hop over the fence and grab some supplies.
26. The same technique works on the previous contraption. Hop onto the trunk. From here you can reach the planks ahead which will lead to another open window.
27. Once inside, you hear Mr. Nutcase reveal himself as Father Gregori. Continue through this doorway to load the next area.
28. Not good. If you're a quicker shot that I, this solitary head crab shouldn't be a problem. Better to shoot the barrels while he's still on the stairs, then back away before the 'splosion.
29. Enter this room on the right and witness Gregori's marksmanship. Supplies are to the left.
30. Tossing a paint can at a zombie won't stop him but it sure looks cool. In addition to the many zombies and head crabs, you'll have to watch out for Gregori's shotgun.
31. Well-timed shots at explosive barrels will help thin the ranks of the undead below. Don't drop down until you're certain the area is clear.
32. Explode this barrel to knock the bars off. Kill the head crabs that emerge, then wait for the flames to die down. Inside are supplies.
33. Climb this ladder at the other end of the alley.
34. Follow the planks to (1) and find supplies plus a head crab. The way ahead is through the window at (2).
35. You'll find more supplies inside, as well as this saw blade and a cinder block. Use them to mow down the zombies blocking your path. Descend these stairs and continue around the corner to load the next area.
36. Once outside, you'll see and hear a new howling zombie variety. Make sure you have a weapon ready as one is about to approach from the stairs ahead.
37. This doorway is the way forward. Clear out the adjoining alleys and train tracks for some optional target practice first. You'll also find some supplies lying about.
38. This building is pretty standard stuff. Keep working you way up the stairs, searching the rooms for supplies and mowing down foes with your SMG.
39. Once on the roof, Gregori will toss you a shotgun. Follow his advice and shoot for the heads of these faster zombies. Jump into the water tank ahead then climb the ladder on the right to the rooftop across the way. You'll find ammunition for your shotgun -- useful as more quick zombies attack. Proceed through the gray door visible to the right.
40. Grab supplies and call the lift. You might want to grab a canister with your gravity gun, as more quick zombies attack while you wait.
41. Defeat the nasty toxic zombie at the bottom and then walk these planks to clear the fence. The toxic zombies throw toxic head crabs that can knock your health down to 1 in a single hit, although the damage does repair over time.
42. Supplies and a head crab are to the right. Continue down the lane to load the next area.
43. This lane is very difficult. Don't try to clear the area of foes. They just keep spawning so it's a losing proposition. Don't waste your ammo.
44. Instead, run toward those barrels ahead, then take the steps to the balcony on the left.
45. Up here you'll find supplies, and this yellow switch. Throw the switch to move the platform into position.
46. Return to the street and follow the arrow to the stacked boxes (inset). Climb the boxes to the rooftop.
47. Jump across to the ladder at (1) then follow the boards to the rooftop at (2).
48. Follow the planks left to the supplies at (1) before following the planks right at (2).
49. Jump across to the platform you moved earlier at (1) and then rush to the ladder at (2). Note the medkits on the way.
50. Climb another short ladder then jump across to the fire escape as indicated.
51. The fire escape collapses but you can hang on. Enter the window on the left.
52. Once inside, you'll have to fight your way past a mob of zombies and down some stairs to load the next area. This was a very difficult sequence. Congratulations for making it this far.