Magic 7: Hard Truths (Magic 7 #4)

Leo, the spiritualist, is spending his vacation at his father's house. In the library, he finds books that delve into the secret origins of the mages, shedding light on their incredible powers, as well as their weaknesses... The truth might be a hard pill to swallow, but this knowledge will prove crucial for the seven friends as they prepare to confront... the beast!