Mistaken Missive

This spell alters the appearance of words written in ink. When the spell is cast upon a written page, the ink imperceptibly begins to move. Over the next few days, the message becomes progressively more illegible. If the page is left undisturbed for six days, an entirely new message forms on the page. The new message is completely legible and is recognizable as the handwriting of the original author, but is contrary in content to the original message.
After the spell is cast, the message will appear different every day. The DM decides the message that the page will carry after the sixth day has passed. Following is a sample of the changes that could take place in a message.
Day One: The words of the letter appear faint, as if the author of the letter was running out of ink as he wrote.
Day Two: The words have moved slightly from their original positions, as if the person writing the letter were shaking or in a moving carriage when the letter was written.
Days Three and Four: The message is gibberish. Although the ink forms groups of letters arranged in lines with punctuation, nearly all the words are meaningless. This may appear to be some sort of code, but it means nothing.
Day Five: The ink has formed real words. However, the sentence construction is still meaningless (e.g., Egg west worse green!).
Day Six (and beyond): The message is coherent, but the opposite intent of the original message has been created. If the original letter read, "Send troops quickly," the new letter reads, "All is fine. Keep your men in reserve."
If mistaken missive is cast on the pages of a spellbook or a scroll, the ink on the page reforms into a new spell of the same level as the original spell. Thus, a darkness spell might become a maze spell. However, the spell formula will be wrong. Although it will look like a proper spell, it will not function when cast.
A coded message that is subjected to mistaken missive will appear as a coded message on the sixth day but will hold a different meaning than the original message.
A glass of preserved words will allow the original message to be read correctly. Dispel magic will restore the message to its original form.

[Tome of Magic]

Sphere: Chaos
(Alteration)
Level: 1

Range: Touch
Components: V, S, M
Duration: Permanent
Casting Time: 1
Area of Effect: One page/ level
Saving Throw: None

Material Components:
three drops of ink