Avalon — Kevin B. Shearer

After the tragic and unexpected loss of Merlin, young Arthur must lead his companions through every peril Morgana and the vast Pacific Ocean can throw at him. Without their teacher, protector and guide, the boys have no way to fully prepare themselves to enter Avalon and face Merlin's dangerous Sisters. What happens in that mysterious realm, even Merlin would not have expected, and though the crew of the Bád Dragain may find an escape, you will never leave.