I'm surprised no one else has noticed this. (I think. \: ) If you play OCH, you can actually play on a level that is normally occupied by a terminal. It says ??? for the depth, but in reality, it goes like this:

• T1:
  1. D3: Storming the Walls
  2. D4: Silence the Guns
  3. D5: Flank the Frontlines
  4. D6: Clear the Gatehouse
  5. D7: Engines of War
  6. D8: Aftermath
• T2:
  1. D13: Storming the Walls
  2. D14: Silence the Guns
  3. D15: Flank the Frontlines
  4. D16: Clear the Gatehouse
  5. D17: Engines of War
  6. D18: Aftermath
• T3:
  1. D24: Storming the Walls
  2. D25: Silence the Guns
  3. D26: Flank the Frontlines
  4. D27: Clear the Gatehouse
  5. D28: Engines of War
  6. D29: Aftermath

The depths in bold are at the terminals. What is odd is how these are accessible this way. I'm certain is goes like this cause I tested it myself. (Ok, I tested a wrench wand at the T1 levels, and it matched up, with the exception of the terminal numbers, which I didn't have recorded.) Just pointing this out, cause it seems interesting.