The Right kind of wrong (Eren x Levi)

Long ago, there lived 4 kings who ruled over the four clans, Blue, Red, Gold, and Silver. These four kings lived in peace and harmony, ruling over their clans. Until one day, the Silvers attacked the Blues, taking their land and their crystal. Once they slivers had assassinated the king of the blues, the silvers became one of the most powerful Clans. 20 years later, Eren Yeager, a 18 year old learns that he was blessed with the power of the Blue king. Once he learns who he truly is, Trouble comes