Light Ink is one of the most widespread uses of magic in the Deceiver Universe. It is an insoluble liquid that changes color based on lighting conditions. When used to write onto paper, the color stays and it is permanently stained with it.
It can be used in conjunction with a contract to draw methods. Light Ink was invented by the God Apollo shortly after contacting humans for the first time, as he was interested by the concept of writing. It can be created by transmuting pure deep-sea water from any planet with a Contract of any kind.