Gargantua's Spells of Enlargement
by John HareFollowing the idea of books which when read would inflict spells of compulsion/servitude here is one possibility.
Gargantua's Spells of Enlargement
This blue leather bound book has the word Gargantua inscribed on the front cover in silver letters. It is 13 inches tall, 2 inches thick and 6 inches wide. Fine vellum inside is inscribed with green ink of some sort. Reading through the book will allow the reader to research spells involving growth, enlargement, etc. with a 5% bonus. However there is a 40% chance that any such book found has actually been treated with a spell of compulsion/servitude to the scriber. A saving throw is made as soon as the first ten pages are read. Failure means that the reader will be able to see the hidden instructions in the book and will read them all. If the initial saving throw is made no further checks are made. Each page in the book may contain an instruction. However each page allows a saving throw not to perform it. However each failed save means a -1 to the roll. Thus reading the tenth instruction means a -9 to the save. Each page may contain up to 100 characters of instruction, including spaces. Thus more complex instructions may take more than one page. A dispel mage will remove the hidden compulsions, however it will also remove all writing including that which a mage would want. The book will detect as magic when checked.
The first compulsion is to begin copying the book which will take roughly a month, minus their skill level in scribing in days (or 1/2 Int). On the first page the scriber puts his/her own name to be the primary controller. Also in the first compulsion is placing every compulsion from the first book that the reader failed in and how to do so.
It is in this way that to trace the book to the one who started it means going through every mage in between. The second instruction generally goes along the line of giving the scriber of the book 100gp a month (depending on campaign resources this could be more money or less time). The third would be buying some sort of rare ingredient from a certain merchant firm in a certain city. This way the master mage will know roughly which mages have fallen under his/her control (complete or partial). The fourth is to make a silver star medallion inset with rubies which thus identifies the member. The fifth is to assist any person displaying the medallion when called upon. The sixth is to always buy any special products from a specific merchant line (which will have factors around most large cities). The seventh to [n-1] are up to the specific campaign, the last compulsion is to sell/give the copied book to another mage either directly or through a merchant. (a merchant known for carrying rare books would be a good idea, or even a special library in a magicians guild)
One way to discover these books is that the compulsion is written using some sort of invisible ink and thus can be detected with a detect invisible spell. And since the scribe's name is clearly shown on the first page allows the trace of the books to begin.
Now you just have to figure out who your master mage is and how wide spread the compulsion is. If a guild has been affected then those who are called upon to help a fellow star wearer could be substantial. There might be an added compulsion to read other books which may have changes or amendments to the first compulsions, such as if the merchant line has been destroyed or some such.
Of course those who have
successfully read the book and failed their save learn the spell of
compulsion to allow them to duplicate its use. However to prevent
them from running amok in the first compulsion is when they are
allowed to use it.