The Shadow Keeper

Moll Pecksniff and her friends are living as outlaws in a secret cave by the sea, hiding from the Shadowmasks who hunt them. Together with her best friends Alfie and Sid, and her loyal wildcat Gryff, Moll must find the Amulet of Truth, the only thing powerful enough to stop the Shadowmasks and contain their dark magic. Along the way, they must sneak past smugglers, outwit mer creatures, and crack secret codes to save the Old Magic. The Shadow Keeper is the second book in the Unmapped Chronicles series.