Notpron (originally stylized as Not Pr0n) is an online puzzle game and internet riddle created in 2004 by German game developer David Münnich. It has been hailed by fans, journalists, and Münnich himself as "the hardest riddle available on the internet". Regarded as one of the first of the online puzzle game genre, Notpron follows a standard puzzle game layout, where the player is presented with a webpage containing a riddle and must find the answer to the riddle in order to proceed to the next webpage. The game has a total of 138 "levels", ranging from 82 "positive" levels, 44 "negative" levels, and 12 "Greek" levels (Ranging from "Alpha" to "Lambda"). These three level groups do not differ from each other, apart from having different names, though each consecutive level increases in difficulty. Levels consist of finding either a password (known as a "UN/PW" by the game's community) or finding a URL to use in order to proceed to the next level. Passwords do not require a player to create an account but instead are given to a player once they have found the answer to a level's riddle. Each level answer or solution is unique, often requiring specific skills such as decoding ciphers, image editing, musical knowledge, and formerly remote viewing. More information...
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