Phlostigon said:I checked that slave to darkness book(I found a PDF online somewhere), but I couldn't find the table you were talking about. Do you know what page it is on?
Actually one of the characters has something similar to that already. The character grew another head with a different personality as one of his madness affects. Later, a madness affect caused him to switch bodies with one of the other characters. The mind in the second head stayed with him, and now they have to make opposing will saves to control the body.Along the lines of the "character gains multiple personalities" ideas: