Activision has buried the Call of Duty 2020 release under ciphers, puzzles, and challenges. Like a long-forgotten Cold War case file, players are trying to decode formulas from the 60s specifically designed to encode information. Activision has carefully mixed history within its challenges, edging fans ever closer to the full Call of Duty 2020 release trailer.

On the label of the fourth tape is a pink sticker which fans believe links the tapes to various puzzles. As there are no pink puzzles discovered as of yet, fans are instead connecting the fourth Call of Duty 2020 tape to the indigo sticker puzzles that were discovered awhile ago. These puzzles make references to various experiments revolving around: "(λ) & F"

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There are five total parts to these experiments but the best place to start is with the unique name. (λ) & F is also known as Lambda and F does not have many appearances. Lambda is usually used in reference to frequency as the representational form of the inverse relationship to a wavelength. When determining the speed of a wavelength, or its velocity, lambda multiplied by frequency creates an accurate reading of velocity or simply: V = (λ)F.

indigo cipher puzzles call of duty 2020

When looking at the first image, or 1/5, players can see that it is looking for input broadcast values. These most likely refer to either broadcast codes from the station, similar to radio tuning, or values from the literal broadcast themselves on the VHS tapes. The values are numerical and they directly connect to 2/5 and 3/5 as the edges of the grid have exactly the same number of spaces.

This has led many fans to believe that 4/5 is a test code meant to solve 3/5 and 2/5's charts. Once the empty places have been filled in fans can decode the final sequence of "Delta, Echo, Charlie, Golf" and be given a telephone number.

A group of avid puzzle solvers have, reportedly, solved this puzzle and given the phone number to Warzone streamer NoahJ456 which he has called multiple times. Each time it asks for a confirmation code, which he assumes will be found in later puzzles. Seeing as no one has seen the solution the streamer has so far been taking their word for it as a solve. It is possible that the "Bravo, Foxtrot, Alpha" segment of the cipher is the confirmation code that the number wants, but until this puzzle is solved publically it is hard to tell.

Call of Duty 2020 is in development from Treyarch and Raven Software.

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