Comment by chongli

Not just random rumours, there are multiple specific mechanisms built into the game that explain core features, which a curious player can stumble on and then deliberately mine for information.

NetHack in many ways has common heritage with text-based adventure games of the 1970s and 80s, such as Zork. NetHack’s in-game currency is even a reference to Zork! Solving Zork without spoilers is also extremely difficult, despite lacking the tactical combat of NetHack. However, playing Zork with spoilers completely ruins the game, whereas NetHack is still a lot of fun even for highly spoiled players.