You write instructions or other information on parchment, paper, or any suitable writing material. The Illusory Script appears to be some form of foreign or magical writing. Only the person (or people) designated by you at the time of the casting can read the writing; it's unintelligible to any other character.

Any unauthorized Creature attempting to read the script triggers a potent illusory effect and must make a Saving Throw. A successful Saving Throw means the Creature can look away with only a mild sense of disorientation. Failure means the Creature is subject to a Suggestion implanted in the script by you at the time the illusory script spell was cast.

A Suggestion influences the actions of the unauthorized Creature by suggesting a course of activity (limited to a sentence or two). The suggestion must be worded in such a manner as to make the activity sound reasonable. Asking the Creature to do some obviously harmful act automatically negates the effect of the spell.

The Suggestion lasts only 30 minutes. Typical suggestions include “Close the book and leave,” “Forget the existence of this note,” and so forth. If the suggested activity can be completed in a shorter time, the spell ends when the subject finishes what it was asked to do. You can instead specify conditions that will trigger a special activity during the Duration. If the condition is not met before the spell Duration expires, the activity is not performed.

If successfully dispelled by Dispel Magic, the Illusory Script and its secret Message disappear. The hidden Message can be read by a combination of the True Seeing spell with the Read Magic or Comprehend Languages spell.