The game involves helping Sofi, a little girl wandering through her dreams in search of her Nana, who has disappeared from her life. Sofi walks innocently across the screen, to the end of each level. Similar to games like Lemmings, instead of controlling her directly, players control a cursor and use objects such as stairs, trampolines and slingshots to get her across platforms and protect her from enemies. And much like Tetris, these items come randomly, with an icon in the corner showing which object will come next. Players can "hold" one item for use later on, but they cannot discard items.
Within the level there are fireflies that can restore Sofi's health if she is hit by enemies, and which unlock bonus levels if collected in great numbers. If Sofi falls into hazards such as thorns, the player has to restart the level.
The game was released in late 2009 as downloadable content for both the XBox 360 (via the XBox Live Marketplace) and Windows PCs via the Steam online marketplace.
Source: Wikipedia, "Lucidity (video game)", available under the CC-BY-SA License.