Just like in the real world, there are multiple religions present in the Alternate World and although players are not required to join any religion, it is clear that they have very diverse types of religions that anyone can explore and join in without any problem. Even players can do so if they wanted to though they are not forced. But if there are lots of religions, there are two that dominate the majority of religions present in the game and that is the religion that worships the God of Life and the God of Death, though the latter seems to slowly lose its followers though I know some who still do.
However, if there are religions that are considered to be acceptable and normal to the people living in Alternate World, there are also religions that are viewed in a bad light, purely barbaric, heretical, unacceptable, and purely evil in a sense.