XI

"Xi (pronounced (UK) or (US) "zee" in English.) is the world's first console-based and virtual world-based alternate reality game.

It was a one-time-only play, unfolding in real time. The game was an adventure to help find "Jess" and the meaning of Xi by collecting fragments and butterflies found in a series of secret areas in Home that changed frequently.

The game also challenged the users to search for clues in the real world. This game was created by nDreams who released several spaces for Xi. The game was promoted through a teaser campaign of clues and hints during the month before its release on March 23, 2009. The clues were hidden in the Menu Pad and videos in the central meeting point.

The game lasted a total of 12 weeks from its release. Xi and all of the corresponding spaces were exclusive to the European and North American versions of PlayStation Home, though there were also websites, videos, printed media and live events which were accessible to anyone." - Copy from Wikipedia