Iceciro
Special Ability: Decimate
To be honest I would love it if other religions can spread via non-missionaries, it would help the issue of founding first being such a benefit. I imagine the chance would be affected by the civics of the city, and of the city where the religion is coming from - and probably be at a lower chance after the first religion has been established.
Thus, there's still a large place for religious decay - not the least of which a noticeable decay for Atheism is in order since it represents active suppression of religions.
Thus, there's still a large place for religious decay - not the least of which a noticeable decay for Atheism is in order since it represents active suppression of religions.