Ghosthunters and the Muddy Monster of Doom!: Ghosthunters #4

To earn his Ghosthunting Diploma, Tom’s got to nab a deadly Twelfth Messenger. But while on the hunt in the haunted town of Bogpool, Tom stumbles into the mucked-up lair of a mud-loving minotaur who has an entire army of ghosts at his command. Suddenly there’s a lot more at stake than Tom’s graduation. This raging beast is dead-set on doomsday–and that’s no bull!