Platinum Cadre

The Platinum Cadre was an order of dragonborn knights from Tymanther sworn to the service of Bahamut. Because they worshiped a dragon god they were outcasts in tymantheran society and wasn't uncommon that its members were expelled from their clans because of their beliefs.

Beliefs
The Platinum Cadre professed that dragonborn weren't the creations of the dragons of Abeir, but instead were the ancient children of the dragon god Bahamut. As such, members of this group believed that not all dragons were evil, and actively worked to change the prejudices of the tymantheran dragonborn while seeking out for good dragons, in hopes of bridging the divide between them and the dragonborn.

Even when most of the tymantheran dragonborn ridiculed the Platinum Cadre for their beliefs, in fact their members were close to truth, as the dragonborn of Abeir were actually related to the ancient dragonborn of Bahamut, although only a few older dragons knew about this relationship.

History
In 1479 DR, a priestess of the order named Nala claimed to be a priestess of Bahamut but was secretly a priestess of Tiamat. Because most dragonborn knew little about the gods of Toril, they were unable to distinguish the magic of Tiamat from that of Bahamut. Tiamat's power enabled the knights to use their breath more often than most dragonborn, and used this exceptional power to defeat the Ash giants who were attacking Tymanther even though other tymantheran troops, even the Lance Defenders, were defeated by the giants.

The dragonborn warrior Balasar exposed Nala as a Tiamatan and she fled to the Black Ash Plain and sought refuge with the green dragon Skuthosiin. Patrin, a paladin of Bahamut and the leader of the order, was killed in a duel of honor with Medrash, a paladin of Torm, when he refused to acknowledge that Nala was really evil.

Even though the lost of their leader and the discovery of Tiamat's influence was a heavy blow to the Platinum Cadre's reputation, its members remained faithful to Bahamut and with the guide of their new leader, Vishva, and the paladin Medrash, they still served in the army of Tymanther. Even if reluctantly, the tymantheran recognized the members of the Platinum Cadre as some of the best warriors their country had to offer.