This project is about scrambling a secret message or picture in such a way that it can only be decrypted when certain environmental factors are met. The guide covers three different types of sensor inputs: GPS coordinates, lux light values, and temperature/humidity/CO2 readings. The general concept could be adapted for other types of sensors like magnetic, gyroscope, proximity and more.

The inspirations for this project include reverse geo-cache puzzles like the one in this learn guide, and statues that are engineered to use the sun's location at specific day and time to create a special effect with shadows or sun beams. A few historical examples of the latter are ‘the descent of Kukulcán’ serpent effect on the Kukulcán pyramid in Chichén Itzá Mexico, and the inner chamber illumination at Newgrange in County Meath Ireland.

Parts