Reddit user TheMorse_ reported discovering a hidden cutscene in the files of God of War Ragnarök that could be a prologue to the next game in the series. A similar practice has been used before: the introduction to Ragnarök was also hidden in the files of God of War.
According to the author of the find, the hidden scene features certain "higher order" entities and Athena discussing Odin and Atreus. A mysterious character named Robed Figure also appears, uttering the phrase in Greek: "To lefkó fídi tha se fáei" — "The white snake will devour you." The user suggests that this image conceals Athena herself before revealing her face — similar to how Baldur appeared as "Stranger" and Freya as "Hermit Witch" in previous games.
Of particular interest is another character — a certain "Mau" accompanying Atreus on his journey through other pantheons. The creature communicates by repeating only the word "Mau", but those around him understand him — similar to how Groot from "Guardians of the Galaxy" only says "I am Groot". Atreus, it is claimed, is able to understand Mau thanks to his divine gift for languages.