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DOOM 3 Hints

What's the code for the locked door in Combat Preparation?

  • 1 of 3: Like most codes, it's stored in someone's PDA.
  • 2 of 3: However, the PDA with this door code won't be available until you return to Mars City after doing the underground area.
  • 3 of 3: Also, even if you peek ahead to get the code early, it won't work yet. I guess you'll just have to wait until later.