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Part 9
Half-Life: Opposing Force

Part 9

Detailed walkthrough for Part 9 of Half-Life: Opposing Force, covering the Vortigaunt Office Area and optional areas, including enemy encounters and item locations.

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Detailed walkthrough for Part 9 of Half-Life: Opposing Force, covering the Vortigaunt Office Area and optional areas, including enemy encounters and item locations.

Walkthrough
  1. 1
    From the turret room, help your guard kill headcrabs in the hallway.
  2. 2
    Proceed to Section c1a2a: Vortigaunt Office Area.
  3. 3
    At the top of the stairs, recruit a second guard.
  4. 4
    Bash crates for a bullet clip.
  5. 5
    Cautiously enter the red-rimmed doorway; a headcrab will drop, let guards handle it.
  6. 6
    Leave guards behind temporarily. Find an armor battery and health pack in a side room to the left.
  7. 7
    Backtrack to the hallway, lure vortigaunts into the side room by backing up near the EXIT sign, and kill them while they are unable to shoot through the door. Crouch to avoid melee.
  8. 8
    Retrieve your guards.
  9. 9
    Past the side room, find a weak ceiling panel and retreat as a headcrab falls; let guards kill it.
  10. 10
    In the lounge-like room ahead, repeat the process with the ceiling-hid headcrab.
  11. 11
    Shoot a vortigaunt in the lounge's small doorway once, then let guards finish it.
  12. 12
    In the small side office, let a vortigaunt break through the window, then collect bullets from the desk after your guards kill it.
  13. 13
    Go down the hall to the area with two doors (one labeled D-AL 102).
  14. 14
    Lure out and let guards kill the ceiling headcrab in the room without the D-AL 102 door. Use the first aid station if needed.
  15. 15
    In the D-AL 102 room, crowbar a barnacle guarding another door with the same label.
  16. 16
    Enter the scientist's room, find a health pack on the desk, and optionally turn on the lights.
  17. 17
    Return to the lounge, climb onto the couch, bash weak ceiling tiles, and climb the ladder.
  18. 18
    Lure an autoturret to activate, then duck out of sight and use the control box switch to turn it off. Collect shotgun ammo from underneath it.
  19. 19
    Climb back down the ladder.
  20. 20
    Find the exit corridor with vending machines to the left of the lounge.
  21. 21
    Use a grenade to blow up the vortigaunt behind the farthest vending machine.
  22. 22
    Be ready with the shotgun for other vortigaunts past the vending machines.
  23. 23
    Kill the barnacle past the exit corridor with the crowbar.
  24. 24
    Go up the first set of stairs, then slowly up the second set, shooting or grenading the three headcrabs at the top.
  25. 25
    In the next hallway, wait for the zombie to pass the explosive crate, then shoot the crate with the shotgun. Finish the zombie if necessary.
  26. 26
    As you approach the left turn in the corridor, lob a grenade around the corner to kill the two vortigaunts. Double-barrel any survivors.
  27. 27
    Proceed to Section c1a2b: Optional Areas and Zombie Cafeteria.
  28. 28
    Stay left when approaching the door to avoid a headcrab in the vent shaft above.
  29. 29
    Enter the area with a security guard but do not recruit him yet.
  30. 30
    Locate a floor-level vent grating to the left of the entrance. Bash it and crawl through to a fan room.
  31. 31
    Climb the ladder and time your run through the fan blades, crossing when the broken blade is on top.
  32. 32
    Bash the floor grating past the fan, drop down, and move until you reach a wall grating.
  33. 33
    Shoot two headcrabs through the grating before bashing it.
  34. 34
    Bash through another grate, then walk along the top of a vent shaft.
  35. 35
    Look for another grate to bash and go through.
  36. 36
    Past yet another grate is an open area with rusty metal beams. Cross carefully, using the other beams to go around a cable.
  37. 37
    Headcrabs will break through a wall ahead and to the right; shoot any that leap out or fall below, and toss a grenade into the remaining crabs.
Tips
  • Utilize your guards to deal with early headcrab and vortigaunt threats.
  • Crouch when fighting vortigaunts in tight spaces to avoid their melee attacks.
  • Use grenades effectively for groups of enemies or to trigger explosive barrels.
  • Time your movements carefully when navigating hazards like fan blades.
  • Conserve ammunition by letting guards engage enemies when possible.
  • Access to new areas and progression through the game.
  • Collectibles: Bullet clip, armor battery, health packs, shotgun ammo.

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