"The second book in the Bad Unicorn trilogy features killer unicorns, good dragons, rogue fire kittens, and a boy who just might be a wizard"--

After defeating a killer unicorn and saving a universe, all Max and his friends want to do is go home. Instead, Max discovers that the Codex of Infinite Knowability has stopped working. He can't use it to get home until he reboots it. Book #2