Tag Der Toten marked the end of the Aether story that has spanned over 10 years and the easter egg has been solved less than 24 hours after it's release. The Call of the Dead remake was the swan-song for the Call of Duty Zombies saga and the final map. Black Ops 4's DLC 4 was part of the Operation: Dark Divide.
You can also find more Tag Der Toten guides such as:
Tag Der Toten Easter Egg (Spoilers)
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