Hi all, this is a quick guide on how to decrypt the floppy disk for the Operation Chaos side mission in Call of Duty: Black Ops Cold War.

It seems the code to crack the floppy disk is different for all users, but by following this guide you'll crack it in no time.

Acquire the Evidence

The first step to decrypting the floppy disk is to finding all the evidence. You need to find three pieces: Front Page of the Observer (found in the retro bar in the mission "Redlight, Greenlight"), A Coded Message (found after talking with Qasim in the first mission or two in the game), and Numbers Station Broadcast (found in the mission "Brick in the Wall").

Finding the Passphrase

The next step is to find the passphrase. Open the coded message and you'll see a bunch of numbers appear in some of the squares in both red and blue. You'll need to find the pattern in order to figure out what your missing numbers from your sequence is.

To find your missing numbers, split it into red numbers and blue numbers. Find the missing number in the red set first, then the blue set.

My sequence was 68 66 70 71 74 76 ? ? 88 86.

In my sequence, my red numbers increase by +x*2 (where x is that number's position in the sequence after the first number). 68 + 2 = 70, 70 + 4 = 74, 74 + 6 = 80 (my missing red number), 80 + 8 = 88.

My blue numbers were just increasing by 5 each time: 66 + 5 = 71, 71 + 5 = 76, 76 + 5 = 81 (my missing blue number), 81 + 5 = 86).

After this, you will have your missing numbers. Listed to the Numbers Station Broadcast and match them up to one of the cities. The name of the city is your passphrase. Mine was 80 81, which equated to "Charleston". This makes "charleston" my passphrase.

Finding the Code

The last step is to find the code. Inspect the newspaper and you'll notice some of the letters in the headline turn red. Write them down and unscramble them to match the name of a city (a list of these is within the Numbers Station Broadcast). Once you find the city, find its corresponding code from the Numbers Station Broadcast. This is the code you need.

My highlighted letters, unscrambled, gave me "Portland", which had a code of 84 90. This means 8490 is my code.