The Guardian Chronicles

When the Gods first created the world of Bremaria, it was decided to leave its inhabitants free to choose between good and evil. The Light Races, represented by humans, elves, dwarves, halflings, and troglodytes, were balanced by the Dark Races; goblins, hobgoblins, trolls, ogres, and gremlins. Other races, most notably the dragons, centaur and minotaur, were created in neutrality (although even they may lean to one side or another). It was made known that in time to come, the Gods would return to judge the world, and to decide its ultimate fate. In order to help the races lean towards good, it was decided to bequeath to one of the race of dragons the power to be omnipresent in all beings of every race, knowing the deeds, desires, and motivations of all people, everywhere. That dragon became the first of the Guardians.
Vast wisdom and knowledge was granted to the Guardian, as well as much greater magical powers, a lifespan thrice that of normal dragons, and the ability to pass on their powers at the time of their death to an apprentice of their choosing. They were to use their powers and knowledge not to dominate the races, but to persuade them to live in peace with one another, and to make the world what the Gods had intended it to be.
The Guardian Chronicles trilogy details a part of the history of Bremaria. It specifically deals with a time of great upheaval and warfare which occurred almost a thousand years after the Guardians had finally brought true peace to the land. Book One, The Chosen of the Guardian, begins with the current Guardian; Gangar, a golden dragon of great age. Deeply attached to Bremaria and its people, he had waited almost too late to choose an apprentice. In his haste to do so, he picked Trantyricus the Black, a young dragon of great power, ability, and charm. But there was a darker side to the new apprentice, which his master knew nothing of (the powers of the Guardian being limited in their ability with regards to dragons, as opposed to common mortals).
Dismissing his troubling behavior as the arrogance typical of youth, Gangar taught his student how to experience the world through the eyes of its lesser inhabitants, as the Guardians themselves do. He hoped that in feeling firsthand the hopes, tragedies, fears, and love of others, his student's proud and arrogant nature would be tempered by compassion. He was wrong.
Trantyricus reveled in the suffering of others. And in playing with his victims, he finally discovered that he could also take complete control of them, and make them do his bidding. Using others to amuse himself, he eventually went too far, causing a conflict which resulted in the destruction of an entire city. Gangar was horrified, and cast his student out. But it was already too late.
Using his former master's teachings as a base to build his power, Trantyricus has, at the time our story begins, taken control of the Dark Races, which are more susceptible to his summons, an...