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Half-Life: Opposing Force

Half-Life: Opposing Force

By ···10 min read·Multi-source verified
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Welcome to Half-Life: Opposing Force, the 1999 expansion that puts you in the boots of Corporal Adrian Shephard. You'll be fighting through the alien landscape of Xen and Black Mesa as a Black Ops soldier, wielding new weapons like the Displacer Cannon and facing off against both alien creatures and the HECU Marines you once called allies. It's a gripping, atmospheric first-person shooter with a fantastic soundtrack, and this guide is here to help you master its challenges.

We'll cover everything you need to know to conquer this story-rich campaign. From navigating the early Xen chapters to understanding the advanced combat scenarios and utilizing every weapon effectively, this guide provides comprehensive walkthroughs and strategies. Get ready to uncover secrets and overcome every difficult encounter as you fight your way through the chaos.

Part 1

Detailed walkthrough for Part 1 of Half-Life: Opposing Force. Learn strategies, tips, and secrets to navigate the early missions of the game.

This is a very complete walkthrough of Half-Life: Opposing Force, including tips, strategies, and secrets. The author prioritizes taking minimal damage and using ammo efficiently, while aiming to skip as little as possible. The walkthrough covers differences between game versions, including the Steam Source version.

Walkthrough
  1. 1
    The guide begins with Part 1, detailing the initial sections of the game.
  2. 2
    Specific updates for Version 1.50 include notes on skipping section c1a2c, opening the silo door early in c1a3, using a rail car to reach an exit pipe in c1a4, using a barnacle for a secret area in c1a4i, using tripmines to cross a barricade in c2a1, setting up tripmines before descending a lift in c2a1a, reaching an activation switch faster in c2a1, finding a tripmine with a bullsquid in c2a2b2, a shortcut for launching a rocket in c2a2h, a secret side room near an ichthyosaur tank in c3a1a, and a gauss gun altfire strategy in c4a2a.
  3. 3
    Version 1.45 added a tip about a secret area with three armor batteries in section c2a2d.
  4. 4
    Version 1.4 added notes on differences in the Steam Source version, indicated by "SRC:", including improved physics, altered enemy trigger points, more wandering creatures, and increased enemy combat freedom.
Tips
  • Always check official host websites for the latest version of the walkthrough.
  • For printing, use the RTF or PDF versions for better formatting.
  • Consider using the Universal Hint System for specific hints without spoilers.
  • Quicksave often to avoid losing progress.
  • If you have a favorite strategy or secret, email the author for potential inclusion.

Part 2

Your trusted guide to Half-Life: Opposing Force Part 2. Get expert tips and strategies to overcome challenges and secrets in this critical section of the game.

Hey there! Welcome to Part 2 of our Half-Life: Opposing Force walkthrough. This section is all about helping you get through the game smoothly, with tips and tricks I've picked up over the years. We'll cover everything from specific level strategies to general gameplay advice.

How This Walkthrough is Organized:

The game itself is broken down into chapters, and I've followed that structure here. Each chapter has smaller sections, marked by a "LOADING..." screen in-game. I've used the internal codenames for these sections (like 'c1a0c') because if you're playing on PC, you can use the console's 'status' command to see exactly where you are. Don't worry if you're not familiar with the console; each section also has a brief descriptive name to help you figure it out.

Essential Controls to Master:

Before we dive in, make sure you're comfortable with quicksaving and quickloading. You can check and change these keybinds in the main menu under 'Configuration' > 'Controls'. I highly recommend setting quicksave to F5 and quickload to F8 or F9 – it keeps them from being too close together and is pretty standard practice.

Boosting Visibility:

To make things easier to see, especially in darker areas, head to the 'Options' menu, then 'Video', and adjust the brightness. You'll want to move the gamma slider all the way to the right (or left, depending on the menu – the goal is maximum brightness). This really helps spot enemies and details without washing out the colors.

General Combat Tips:

  • Marines and Vortigaunts can attack from a distance, so always be aware of your surroundings.
  • Marines tend to be less trigger-happy with grenades when you're not in their direct line of sight.
  • Remember that Crossbow darts are affected by gravity, and the Hornet Gun's shots can be a bit unpredictable, making them less ideal for precise, long-range sneak attacks.
  • You can no longer use tripmines you've placed as stepping stones, but any that were already in the environment can still be used.

We've got a lot to cover, so let's get started!

Part 3

Master Half-Life: Opposing Force Part 3 with our comprehensive walkthrough. Learn essential moves like jump-crouching, crouch-running, and sneak-shooting to overcome challenges.

This guide section covers essential movement techniques and early gameplay in Half-Life: Opposing Force, including the Hazard Course, Black Mesa Inbound, and Anomalous Materials chapters.

Key Concepts:

  1. Jump-crouching (Duck Jumping): Essential for navigating obstacles. Combine jumping and crouching.
  2. Crouch-running: Moving while holding the 'Duck' key, but not the 'Walk' key. Faster than true crouch-walking.
  3. True Crouch-walking: Moving very slowly using both 'Duck' and 'Walk' keys simultaneously. Useful for stealth but often not necessary.
  4. Sneak-shooting: Attacking unaware enemies by targeting small, exposed body parts. Allows you to shoot without alerting them, especially effective with the Hornet Gun around corners or through obstacles.
  5. Lift Glitch: A rare bug where you might get frozen on a moving lift. To avoid it, avoid crouching on lifts while they are moving. Jumping just before the lift stops may help.
Walkthrough
  1. 1
    Hazard Course (SRC: Training Room): Recommended for new players to learn jump-crouching and crouch-jumping.
  2. 2
    Black Mesa Inbound (Sections c0a0 - c0a0d): RIDING TO WORK
    • This is the initial tram ride. No actions are required, but you can observe the scenery.
  3. 3
    You'll see a security guard, and later, the G-Man (nicknamed "Briefcase Bastard") in an adjacent tram car.
  4. 4
    Black Mesa Inbound (Section c0a0e): BEING LET IN
    • After the tram stops, follow the security guard.
  5. 5
    Exit the tram and follow him to a reinforced door, then to another door. Wait for the "Anomalous Materials" chapter to begin.
  6. 6
    Anomalous Materials (Section c1a0): STARTING FUN
    • Go through the door and approach the security desk.
  7. 7
    After the guard finishes speaking, use the 'Use item' key on the desk to press a hidden button and briefly sound an alarm.
  8. 8
    You can interact with the communications console for humorous effects.
  9. 9
    Proceed down the corridor with colored stripes on the walls.
  10. 10
    You can explore a computer room to the left and follow the brown stripe past rooms to a guarded door.
  11. 11
    You can attempt to listen to the G-Man's conversation or turn off lights in another room.
  12. 12
    Return to the corridor junction and go down the small ramp to section c1a0d.
  13. 13
    Anomalous Materials (Section c1a0d): GET YOUR HEV ON
    • Turn right past the ramp and follow the green stripe to the break room.
  14. 14
    Face the microwave oven and repeatedly press the 'Use item' key to make the casserole inside explode. This may trigger a comment from an NPC.

Notes:

  • The source text mentions that dead bodies are invincible in this game, contrary to a detail in Half-Life 2.
  • The lift glitch is mentioned as a potential issue, though the source also notes it never happens.

Part 4

Follow the green wall stripe to find the HEV suit room and prepare for action in Half-Life: Opposing Force Part 4.

Walkthrough
  1. 1
    Leave the break room and follow the green wall stripe to the employee locker room.
  2. 2
    In the back left corner of the locker room, use the HEV suit room's control panel to open a case with a suit inside.
  3. 3
    Walk into the case to put on the HEV suit.
  4. 4
    Find the locker labeled "Freeman" near the bathroom entrance, open its door, and go inside to pick up an armor battery.
  5. 5
    Check the wall-mounted first aid station (skip if health is 100) around the corner.
  6. 6
    Go back the way you came, then proceed down the corridor with the blue wall stripe to the security post.
  7. 7
    The guard will open the nearby security door once you have your HEV suit on.
  8. 8
    Go through the security door and the next door to load section c1a0a.
  9. 9
    In section c1a0a, use the button panel to the left of some doors to open them.
  10. 10
    Get on the lift past the doors and use its button to descend to a lower level (or climb down the side ladder).
  11. 11
    Go through some doors and down a corridor until section c1a0b loads.
  12. 12
    In section c1a0b, enter the control room and wait for three scientists to talk.
  13. 13
    After a scientist uses a retinal scanner, go through the unlocked door.
  14. 14
    Find two scientists discussing equipment problems.
  15. 15
    Across from them, use a button panel to summon a lift, then use its button panel to go up a level.
  16. 16
    Exit the lift and go down the corridor until the test chamber door loads section c1a0e.
  17. 17
    In section c1a0e, enter the test chamber's outer room and wait for two scientists to open the main test chamber doors.
  18. 18
    Go through the main doors and across the chamber to a small ramp.
  19. 19
    Climb the ladder on the wall past the ramp to reach an upper walkway.
  20. 20
    Use the walkway's computer panel and wait for the red glass cover (press the cover button to crouch behind walls or objects) on the button to rise.
  21. 21
    Use the button to power up the scanning machine.
  22. 22
    Climb back down the ladder and stand next to the cage near the ramp's bottom.
  23. 23
    When the "specimen" arrives, do a quicksave.
  24. 24
    Get behind the specimen's mounting gadget and push it into the scanning beam.
  25. 25
    Move back a bit and wait to be teleported to border world locations, leading to the "Unforeseen Consequences" chapter.
  26. 26
    In section c1a0c, check if a vortigaunt is in the test chamber ruins with you; if so, restore your quicksave and repeat the teleportation process.
  27. 27
    Leave the test chamber through the jammed-open doors.
  28. 28
    Try using the retinal scan device next to the exit door to open it.
  29. 29
    Go through the door and find a scientist trying to revive a security guard.
  30. 30
    Go around the corner and move forward slowly.
  31. 31
    After a computer bank falls over, jump over the debris in the corridor leading to the lift.
  32. 32
    Get in the lift and use its button.
  33. 33
    Go through the doors and over to two scientists.
  34. 34
    After they finish talking, get the scientist (Dr. Vance) to follow you to the control room door's retinal scanner.
  35. 35
    After he opens the door, move into the room and wait for an electrical surge to blow up the door at the other end.
  36. 36
    Carefully time your run across the room to avoid being zapped.
  37. 37
    In the next hallway, section c1a1 will load.
  38. 38
    In section c1a1, run through the next room quickly as a headcrab will teleport in.
  39. 39
    In the next hallway, crouch-walk under the first red laser beam.
  40. 40
    Run around the second laser beam after it breaks free and slices through a security guard's body.
  41. 41
    Pick up the crowbar next to the nearby doors.
  42. 42
    Go back past the two laser beams to the room where the headcrab teleported.
  43. 43
    Quicksave before entering the room.
  44. 44
    If the headcrab is levitating, go around the fallen pillar, right-strafe to dodge its leap, turn, run up to it, crouch, and crowbar-whack it.
Tips
  • First aid stations make a "hee-yee-hee-yee" sound when used unless your health is 100.
  • The security guard you can potentially take with you cannot get over nearby rubble.
  • Do not pull the specimen's mounting gadget out of the scanning beam after pushing it in, as this will almost certainly cause a vortigaunt to appear.
  • If a headcrab teleports into a room and you have no weapon, exit the room as quickly as possible.
  • If the headcrab is levitating, you must dodge its leap and then quickly attack it with the crowbar before it can react again.

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