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Part 20
Half-Life

Part 20

Navigate Half-Life Part 20, facing marines, houndeyes, and environmental hazards. Learn tripmine placement and combat strategies.

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Navigate Half-Life Part 20, facing marines, houndeyes, and environmental hazards. Learn tripmine placement and combat strategies.

Walkthrough
  1. 1
    When marines emerge from a doorway, let the first be killed by a tripmine. Quickly use a double-barrel shotgun on any subsequent marines. Staying crouched prevents them from immediately firing, providing an advantage.
  2. 2
    After the fighting stops, equip the .357 Magnum and cautiously return to the doorway. Eliminate any marines near the doorway with headshots.
  3. 3
    Position yourself against the left edge of the doorway and look down the passage to the right. Shoot the computer bank on the left wall past a doorway until it breaks, then wait for it to emit a continuous stream of fire.
  4. 4
    Run down and jump over the fire stream. Move against the wall next to it to draw out any noticing marines.
  5. 5
    If marines appear, retreat to the bottom of nearby stairs and watch for grenades. Finish any marines who survive the flames with the assault rifle.
  6. 6
    If a grenade destroys a vent grating over the stairs, immediately shoot the three headcrabs that drop down.
  7. 7
    Return to the position next to the fire stream. Use quicksave and quickrestore to potentially trigger more marines to charge.
  8. 8
    Jump over the flames and search the area to confirm all marines are defeated.
  9. 9
    Jump back over the flames and break open crates in the area past the stairs to find ammo, tripmines, and grenades.
  10. 10
    Break crates in the radio niche near the other side of the flames. Find an HEV recharger and a health pack past the large room with radio equipment and a lift.
  11. 11
    To proceed, set three tripmines: the first to the right of the explosive crates near the area's start, the second to the right of the doorway after returning up the ramps, and the third underneath a red light to the right of that doorway (this third one is less useful).
  12. 12
    Use the lift's control panel to start its descent. Get on the lift with the assault rifle equipped.
  13. 13
    As the lift descends, watch for houndeyes on the nearby walkway and kill them before they detonate tripmines around the lift's base.
  14. 14
    After the lift stops, move off it and wait for it to ascend.
  15. 15
    Once all nearby houndeyes are dead, drop into the water and climb a ladder to the walkway.
  16. 16
    Perform another houndeye check. Shoot explosive barrels visible down the walkway before proceeding that way.
  17. 17
    Wait near where the barrels were for more houndeyes to appear, then finish them off.
  18. 18
    Go down a ramp to find stairs. Proceed halfway down, turn left, and use the pistol to kill a distant headcrab.
  19. 19
    Continue to the bottom of the stairs and stop just before reaching the water.
  20. 20
    While on the last stair not underwater, edge towards the watery area to spot a power generator machine in the distance.
  21. 21
    Turn on your flashlight to see better. Use the pistol to shoot the rightmost of the two wooden crates next to the generator.
  22. 22
    Once the crate breaks and the generator activates, return to the top of the stairs where you shot the headcrab.
  23. 23
    Use the first aid station on the right wall if needed, then enter the room with the power generator console.
  24. 24
    Use the button panel to the left of the console to activate its green light.
  25. 25
    Turn around and time your movement to run past the periodically firing electrical bolt.
  26. 26
    You can use one of the two fans to return to the upper floor, though it is difficult. Alternatively, return to the top of the stairs and walk along the walkway leading to the lift.
  27. 27
    As you approach the lift, it will lower with two marines. Let one see you, then immediately break line of sight. The marine should hit a tripmine, potentially killing both. Be ready with the assault rifle to finish off any survivors.
  28. 28
    Alternatively, after the lift starts lowering, move back to see the nearest low-set tripmine but not the marines. Shooting this tripmine with the pistol as the lift stops should kill both marines.
  29. 29
    After the lift finishes ascending, use the button panel on the other side of its walkway to summon it.
  30. 30
    When it descends again, get on it.
Tips
  • If you blew up explosive crates earlier, the headcrab-and-tripmine strategy is not useful.
  • Staying crouched when marines emerge can prevent them from immediately firing, giving you a tactical advantage.
  • The .357 Magnum is effective for quick kills on marines near doorways.
  • The computer bank emits a continuous stream of fire when activated.
  • Marines can sometimes survive the flames; be prepared to finish them with the assault rifle.
  • Be ready to shoot headcrabs that drop from vents if a grenade detonates the grating.
  • Quicksave and quickrestore near the fire stream can trigger more marines to appear.
  • Breaking crates in various areas yields ammo, tripmines, and grenades.
  • An HEV recharger and a health pack are available past the radio equipment room.
  • Placing tripmines strategically can eliminate approaching marines.
  • Houndeyes can detonate tripmines; prioritize eliminating them.
  • Explosive barrels can be used against enemies.
  • The flashlight is useful for spotting the power generator machine in the dark, watery area.
  • Timing your run past electrical bolts is crucial for progression.
  • Shooting a tripmine with the pistol as the lift stops can kill the marines on it.

Alternative Strategy:

  • After blowing up explosive crates upon entering the area, place a laser tripmine near the red-railed balcony.
  • If placed correctly, you can jump onto the tripmine and then to the balcony.
  • Quickly shotgun-blast the marine around the corner.
  • Shoot the "eternal flame" machine and use it to defeat other marines.
  • This method is trickier due to precise tripmine placement.

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