Hello Games, the developer of No Man’s Sky, has been sending packages to mods of the NMS subreddit that contain, among other things, a cassette tape with a cryptic message.
The tapes, which are numbered out of 16, contain some mysterious audio that, when run through a spectrograph, reveal the set of characters: 706s7274616p. When that is run through an ROT13 cipher, it translates to the hexadecimal string: 706f7274616c. When converted to ASCII the string then turns up the word: portal.
Only a few of the tapes have been accounted for and their audio uploaded but so far all of them have come up with the same word, which at least alludes to the possibility of some new content coming for the game in the near future as the last major update to the game was introduced back in March. With E3 only a few days away, it’s possible that we’ll find out exactly what’s in store for the game soon.