Isle of the dead. Emily Rodda. 2004.

Aided by the mysterious magic of Deltora’s last dragons, Lief, Barda and Jasmine have found and destroyed two of the Four Sisters, evil Shadow Lord creations which have been poisoning Deltora. Now, aware that time is running out for the kingdom’s starving people, the companions are racing to their next goal, on the Wild West coast. 

But the Shadow Lord has become aware of their quest. And somehow, he knows every move they make. Terrible dangers from the present and the past lie in wait for them. And the greatest shock of all lurks in the lair of the ferocious Kobb, on the desolate Isle of the Dead.