Dragonstar: The Dualists
There are two splinter sects in the Dragon Empire who don't believe in the Twelve. They're known as the Dualists.
The Dualist Heresy, as their faith is called, carried the Unification Church's theology one step further. The Dualists argue that the myriad deities—including the Twelve—are merely aspects of two supreme beings. They call these deities the Creator and the Adversary. The Dualist Heresy teaches that these two represent all the oppositional forces of the universe: order and chaos, good and evil, light and dark, positive and negative.
The Dualist Heresy also claims that two is the smallest number of gods possible: One god could not express the opposition that obviously exists in the universe without being self-contradicting. Further, opposites are necessary to define each other. If there was no shadow, for instance, how could there be light? If there was no chaos, how could you define order? Without evil, there is no good.
The Dragon Empire has never endorsed the Dualist Heresy, but neither is it suppressed. In fact, a few prominent dragons are Dualists, and I suspect there are many more who worship the Creator or Adversary privately.
The Dualists and the Unification Church, of course, are constantly at odds. I mean, the whole point of the Unification Church is, well, unification: Many church clerics believe that the very existence of a splinter faith undermines their theology. For their part, the Dualists face the same challenges and obstacles confronted by all marginalized minorities. They struggle for tolerance, converts, and sometimes merely to be taken seriously. As a result, Dualists are often somewhat confrontational, as if everyone in the galaxy who doesn't believe as they do is against them. Their clergy tends to be more militant than that of the Unification Church, especially when it comes to proselytizing.
The Dualist Heresy is in turn marked by a division within its own ranks. While Dualist doctrine teaches the opposition of Creator and Adversary, it ascribes a morally superior position to neither. Most Dualists align themselves with one or the other, though the "purists" preach that Dualism is morally neutral and that "true disciples" of Dualism honor the oppositional totality, not just one side of it.
In some cases, entire worlds have been converted to Dualism. Such places can be dangerous for nonbelievers, although visitors are usually allowed to pass through without trouble. Those who stay on these worlds for any length of time, however, are inevitably pressured to convert—and usually to choose sides between the followers of the Creator and those of the Adversary.
Those who worship the Creator are usually very open. They wear their religious symbols proudly and are fond of quoting the Dualist Scriptures or the popular sermons of their priests and prophets. These faithful are more or less tolerated by others in the Empire: Most people have nothing against those who worship the positive themes of the cosmos.
Worshippers of the Adversary, though, often keep their beliefs hidden from those around them, unless they are surrounded entirely by others who share their beliefs. These dark souls revel in and celebrate evil, entropy, and destruction, and they view others, ultimately, as their enemies, victims, or slaves.