One holds the key, one holds the power. Kaison inherited the magical halberd the day his parents were murdered. Now, he and his sister must infiltrate Sun Castle to uncover their family’s secrets. But Mortimer - an exiled knight with notorious powers - will stop at nothing to take the halberd for himself. On the night of an assassination attempt, a warning is written in the night sky, and a mysterious girl arrives at Sun Castle with magic resembling Mortimer’s. Kaison and his friends soon realize that the magic they possess can destroy their entire world, and in order to defeat their enemies, one of them must become the darkness itself.

The door has been opened, but it is only the beginning. The army of Larkesh saw the Light of Solaris and is coming to take it for themselves. Kaison must not only protect the door but also protect his kingdom, his queen, and ensure his own survival. As the truth continues to unravel, he doesn't know who is his enemy and who is his friend. In Larkesh, Osiris is awaiting her execution in the Vynx tournament. However, one Captain offers her a deal for her survival – kill the designated protector. When Osiris’ best friend is captured by the enemy, she is forced to play all sides to ensure his freedom and achieve her ultimate goal – create a new kingdom where her people are safe. But that leaves her with an unbearable choice dividing not only her mind but her heart – does she side with Kaison or the Shadow of Eclipse?

Kaison has discovered what’s behind the door - a portal to another world. Forced to work with Osiris, Kaison sets out on a new quest to protect his world once and for all. Soon, he uncovers a dark secret and learns he isn’t the only Designated Protector. Osiris has one goal - save her people and create a new kingdom. She only needs to get home to Morbaeda first. But the secret that Kaison unearths could thwart her plans, and she must decide whose side she is on. With Kaison gone, Maeve is forced to move on and unite the kingdom. In order to succeed, she must face the Shadow of Eclipse on her own.