Magnimar's many Mystery Cultists are devoted to various angels, agathions, and azatas. Ashava, Soralyon, and Ylimancha are the most commonly worshiped, but various smaller cults are devoted to other empyreal lords.
These esoteric faithful are small in number, and tend to keep their faiths to themselves, rarely proselytizing their faith. These cultists hold one of Magnimar's many monuments in reverence, and will sometimes gather in great assemblies around the Irespan, Arvensoar, or Mistress of Angels that number over a hundred faithful. Despite their small numbers, odd traditions, and the inconveniences their gatherings may cause, the mystery cults are not prosecuted due to their virtuous beliefs.1
Paizo published an article about the Magnimarian Mystery Cults in Disciple's Doctrine 14f.
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