The Dragon Knight Series by D.C. Clemens

His memories only go as far back to his days slaying starved beasts and mad men in a dark pit, but soon after he’s sold to a criminal syndicate, Mercer gains a chance to avenge the life he lost. Helping him take advantage of the opportunity is an enchanted longsword he finds deep within a mountain, whose power links to that of an ancient dragon. If Mercer hopes to achieve retribution against his formidable foes, he must become something not seen in centuries—a dragon knight.

With a growing reserve of cryptic clues, odd allies, and new memories, Mercer inches closer to learning where he came from and achieving the reprisal he seeks. Entwined with his past and the answers he chases is the Advent, an enigmatic cult who aspire to raise an ancient being said to be on par with a god. They spread chaos wherever their powerful cultists appear, having no interest but to attain the immense power they need to resurrect their lost deity... moreWith a growing reserve of cryptic clues, odd allies, and new memories, Mercer inches closer to learning where he came from and achieving the reprisal he seeks. Entwined with his past and the answers he chases is the Advent, an enigmatic cult who aspire to raise an ancient being said to be on par with a god. They spread chaos wherever their powerful cultists appear, having no interest but to attain the immense power they need to resurrect their lost deity. With an enemy whose plans date back decades or more, perhaps even unleashing a dragon won’t be enough to stop them. less

With the support of a former king and his resources, Mercer Eberwolf must sail halfway across the world to reach a fabled tomb held by the Advent. Rough seas, a vice-ridden nation, and jagged mountains hinder his path. However, even with a wealthy kingdom's aid, the young dragon knight realizes he will need to summon his fire-breathing ally in order to match his enemy's power and purpose... moreWith the support of a former king and his resources, Mercer Eberwolf must sail halfway across the world to reach a fabled tomb held by the Advent. Rough seas, a vice-ridden nation, and jagged mountains hinder his path. However, even with a wealthy kingdom's aid, the young dragon knight realizes he will need to summon his fire-breathing ally in order to match his enemy's power and purpose. Meanwhile, nations eager to test Alslana's new leadership wage a war that threatens to engulf the kingdom abetting his journey. What had once began as a forlorn mission to discover his place in the world has become a race to defend Orda from an all-encompassing change the Advent wish to bring. less