5, Dread MountainBook - 2012
On his sixteenth birthday, Lief and his companions must venture into the darkest and most terrible places in all of Deltora to find the seven magical gems stolen from the Belt of Deltora. When reunited in the Belt, these gems-an amethyst, a topaz, a diamond, a ruby, an opal, a lapis lazuli, and an emerald-will empower the heir to the throne of Deltora and free the people from the evil tyranny of the Shadow Lord.
Four gems have been found. To find the fifth stone, the heroes must venture to the edge of the Shadowlands and enter the dark and terrifying realm of the monster Gellik. Can Lief, Barda, and Jasmine survive Dread Mountain?