The Doorways Trilogy

When Zach Black discovers a doorway, he enters a world similar, yet very different from his own. A world inhabited with vampires, werewolves, and zombies, Zach makes a journey like no other. With the help of a beautiful vampire named Neanna Cera and a werewolf called William Weaver, Zach's journey to save the person he loves takes him through the Doorways. But the Doorways have the power to change you - altering your appearance and abilities as you pass between them.

With a werewolf and a vampire for company, Zach Black makes his way across a vast apocalyptic wasteland in search of the box which contains the Heart of Endra. In the desert, they stumble across a mechanical man who tells Zach and his friends that if they want to reach the box, they will have to cross a desolate land inhabited by terrifying creatures, which have been smuggled from the other side of the doorways.

Trapped by the Delf and her legion of dead-peacekeepers, Zach Black and his friends realize that one of them is a traitor...but who? With the vampire, Neanna Cera, suddenly missing, suspicion soon falls on her.