Blessed One heresy
Some of the the Nine, such as Maylar and Zarthus have many favored souls and some such as Khemra and Hallisan have few. Phidas is the only one of the Nine to have zero favored souls. There are no historical mentions of a favored souls of Phidas in either the First Age, Second Age, or the the Third Age. Many Lanterns and others who dislike Phidas state that Phidas has no favored souls because Phidas is physically and/or spiritually incapable of empowering favored souls. Perhaps because of the wound Turoch inflicted on him. The Masks official explanation is that Phidas has no favored souls because Phidas neither needs nor wants favored souls. They take more power than theurgists to create and are less controllable to boot. Why would any self respecting god or goddess bother with them? The Blessed One Heresy is a collection of Phidas worshipers who believes that Phidas will have a favored soul at some point in the future and when this occurs, he or she will usher in a golden age of prosperity for Phidas' faithful. Besides suppression by orthodox Masks and the derision of other priesthoods, the Blessed Seekers have a major obstacle preventing them from establishing themselves as a true political or ecclesiastical force, themselves. The Seekers do not agree on what preconditions are necessary to preempt the birth of a the Blessed One. Some believe the Blessed One will be a mortal/spirit hybrid so they seek to couple with Phidas spirits. Some believe the way will be paved by the blood of Phidas' enemies which usually leads Seekers to try to murder whomever they perceive as Phidas' enemies. Some believe the Blessed One must be born as a crown prince or princess and seek to convert as many high born noble families to their cause as possible. Some believe that the Blessed Ones must convert a certain percentage of the general population so they work on converting peasantry en masse. Some have heard the myths of the Tiamalan kobolds and believe that maybe the Blessed One will be a kobold. There are less logical and more esoteric ideas on preconditions needed so the Seekers are kind of a chaotic mess.
To prepare the way for Phidas' Blessed One and protect and aid him or her when she arrives.
As of yet, no major secular ruler has publicly endorsed the Blessed One Heresy though there are rumors that some powerful people are closeted followers. The orthodox Masks would like to stamp out the heretics but at the same time, they are reluctant to use the full force of violence they have available to stamp out the heretics. The heretics may be misguided, but their faith in Phidas is pure. Phidas doesn't have enough fervent worshipers that the they can afford to wantonly kill their own.