Witchlings #2: The Golden Frog Games

Every four years, the Twelve Towns gather for a legendary magical tournament — the Golden Frog Games.
With Ravenskill hosting this year's games, all eyes are on Seven Salazar, Valley Pepperhorn and Thorn Laroux: the most famous Spares in the Twelve Towns. Thorn is ready to compete as a fashion champion, but when a forbidden hex is used to turn her fellow champions to stone, suspicion lands on the Witchlings.
As the Witchlings attempt to unravel the mystery of the stonifications, future Uncle Seven is harboring a dangerous secret: While she's supposed to be able to communicate with animals, the voices she hears most clearly belong to monstruos, and one spine-chilling voice is the loudest of all.
Can Seven fix her broken magic and find out who is stonifying the champions . . . before Thorn becomes the next victim?