Impossible Cube
When a creature with an Intelligence score of 6 or higher sees the cube for the first time it makes a DC 10 Wisdom _saving throw_ or becomes compelled to study the cube further. When a creature first studies the cube, it makes a DC 15 Wisdom saving throw or suffers from the Terrorized short-term _mental stress effect_ and a compulsion to study the cube even further. A creature that fails this saving throw by 5 or more instead suffers from the Distorted Perceptions long-term mental stress effect. Any further inspection of the cube has no additional effect.