Church of the Flying Spaghetti Monster

There can be a debate about what is a religion.

One simple test is it's a "Tier 1" religion if many of its adherents have either killed or been killed for their faith.

Christianity, Islam, Judaism, Hinduism, Buddhism, Baha'i, Zoroastrianism, and others meet this criteria.

I don't think the church of the Flying Spaghetti Monster has met this criteria.