The Rhombus of Ruin is a part of the ocean where legends of many ships and vehicles crashing are from, much like its real world counterparts, the Bermuda Triangle and the Dragon's Triangle. It is the main setting of Psychonauts: In the Rhombus of Ruin, as the game's name suggests. The cause of these incidents is the large brain-like deposit of Psilerium at the heart of the Rhombus of Ruin, and the Psychonauts have an old abandoned facility there where they used to research the affects of Psilerium.