Funke, Cornelia - Ghosthunters & the Muddy Monster of Doom!

To earn his ghosthunting diploma, Tom has to nab the deadly Twelfth Messenger, but while on the hunt in the haunted town of Bogpool, he stumbles into the mucked-up lair of a mud-loving minotaur who has an entire army of ghosts at his command. Suddenly there is more at stake than Tom’s graduation… One of a series