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Map 12: The Factory
Doom II

Map 12: The Factory

Complete Doom II The Factory walkthrough: find Shotgun, Invisibility Sphere, BFG, Blue Key Card, Yellow Key Card, and secrets.

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Complete Doom II The Factory walkthrough: find Shotgun, Invisibility Sphere, BFG, Blue Key Card, Yellow Key Card, and secrets.

Walkthrough
  1. 1
    Grab the nearby Shotgun.
  2. 2
    Head to the brown rotunda to the right of your start.
  3. 3
    Inside, defeat Shotgunners on ascending ledges.
  4. 4
    At the top, grab an Invisibility Sphere.
  5. 5
    Drop down and exit the rotunda.
  6. 6
    Go to the building with the silver, trapezoidal lift to the south.
  7. 7
    Use the lift to reach a large window with a red brick interior.
  8. 8
    Equip your BFG, use the lift, and run to the opposite end of the room.
  9. 9
    Quickly turn around to face a massive group of Imps appearing from side openings and the entrance.
  10. 10
    Use a couple of BFG blasts to eliminate most Imps, then use your SSG (Super Shotgun) to finish any remaining enemies.
  11. 11
    Examine the alcoves on both sides of the room for extra ammo.
  12. 12
    Head through the door at the end of the room opposite your entry point.
  13. 13
    Turn right and follow the path, killing an Arachnotron.
  14. 14
    Go to where the Arachnotron was, turn left, and head down the path between brick walls, picking up a Box of Shells and killing a second Arachnotron.
  15. 15
    Continue ahead and to the right to find and kill a third Arachnotron.
  16. 16
    Turn around and head in the opposite direction to find and kill a fourth Arachnotron.
  17. 17
    Head past where the fourth Arachnotron was until you reach a corner, turn left, and proceed along another stretch where a fifth and final Arachnotron awaits.
  18. 18
    Just before the fifth Arachnotron and to the right, open the white door.
  19. 19
    Fire a shot inside to alert monsters; safely pick off the Cacodemon that floats near the door from outside.
  20. 20
    Pick off the Imps wandering inside the room from the doorway; some are on the ground ahead and to the right, others are on crates to the right and at the opposite end.
  21. 21
    Once Imps are dead, drop to the ground and kill the Baron of Hell patrolling on the high wooden ledge with the SSG or plasma weapons.
  22. 22
    After the Baron dies, climb the stairs opposite the door you first entered to reach the high ledge.
  23. 23
    Do not take the teleporter here yet.
  24. 24
    Head off the other end of the ledge to land on a crate and grab a Box of Shotgun Shells.
  25. 25
    Drop back down, go up the stairs, and onto the wooden ledge again.
  26. 26
    Turn around and locate a stack of crates with a switch on one of them.
  27. 27
    To the left, find an isolated crate with a Berserk Pack on it.
  28. 28
    Make a running jump onto this crate, grab the Berserk Pack (if needed for health), then turn right and run to the switch and flip it.
  29. 29
    A lift will lower; step on it.
  30. 30
    When the lift rises, stick to the right wall to reach a ledge where you can grab a Chaingun and a Box of Bullets [SECRET 1/4].
  31. 31
    Equip your Plasma Gun.
  32. 32
    Head back to the teleporter in the corner on the high wooden ledge.
  33. 33
    Take the teleporter to a small, enclosed room filled with Imps.
  34. 34
    Wipe them out quickly with the Plasma Gun.
  35. 35
    Hit the skull switch; the room will raise.
  36. 36
    At the top of the structure, in a corner, grab a Supercharge [SECRET 2/4].
  37. 37
    Drop down and head south.
  38. 38
    Look for a Mancubus in a cubbyhole on the left and kill it.
  39. 39
    At the south end of the room, take the passage leading west.
  40. 40
    Use plasma or rockets to take out the Arachnotron guarding the Blue Key Card from a safe distance.
  41. 41
    Grab the Blue Key Card.
  42. 42
    Turn around and head along the passage heading east.
  43. 43
    On your left, watch for a group of six Mancubi; use the BFG if you have enough ammo, otherwise use the SSG from the corner of the nearby wall.
  44. 44
    After killing the Mancubi, find the small building in the south-east corner with red banners and a gargoyle head door.
  45. 45
    Open the door and quickly take out the Chaingunner guarding the Yellow Key Card within.
  46. 46
    Claim the Yellow Key Card.
  47. 47
    Head to the northern passage.
  48. 48
    You will see a Berserk Pack to the left of a corner filled with Lost Souls.
  49. 49
    Shoot down the Lost Souls from a distance.
  50. 50
    Grab the Berserk Pack only if in dire need of health; otherwise, save it for later.
  51. 51
    Go back and face the opening leading north again.
  52. 52
    To the right, find a small wooden door with a red-eyed gargoyle head.
  53. 53
    Equip your Chaingun or Plasma Gun.
  54. 54
    As you enter, turn right and navigate over metal blocks towards an alcove with a Small Cell Ammo pack.
  55. 55
    When you get close, the wall behind the alcove will lower, revealing another Mancubus; be ready to shoot while backing up.
  56. 56
    After killing the Mancubus, claim the Super Shotgun it was guarding.
  57. 57
    Hit the skull switch to exit the room.
  58. 58
    As you exit, directly opposite is another door with blue banners on the side; head through it.
Tips
  • The Invisibility Sphere found early in the level can help you navigate dangerous areas more safely.
  • Save your BFG ammo for large groups of enemies like the Imps in the lift room or the six Mancubi.
  • The SSG is effective for picking off remaining enemies after using the BFG.
  • Be prepared for ambushes when entering new areas or alerting enemies.
  • The Berserk Pack near the Lost Souls should be saved for when you truly need health, as you will return to this area.
  • Shotgun
  • Invisibility Sphere
  • BFG
  • Box of Shells
  • Box of Shotgun Shells
  • Chaingun
  • Box of Bullets [SECRET 1/4]
  • Supercharge [SECRET 2/4]
  • Blue Key Card
  • Yellow Key Card
  • Berserk Pack
  • Super Shotgun
  • Small Cell Ammo

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