The Yanti by Christopher Pike
This is the final book in the Alosha trilogy – which is only a trilogy because the fourth book in the series was never published. These three books should never have been published either. All the core Pike ideas are there: exceptional female protagonist, a unique and compelling mythology, death, violence, technology, magic; but it was like he copied directly from his notebook of ideas and didn’t include a compelling narrative to link them all.
Ali has discovered that a mysterious Entity is masterminding the Shaktra’s attack on Earth, an attack that will kill billions and leave both Earth and the elemental world shattered. The Shaktra commands vast armies and a host of dragons. Ali has known of her fairy powers for only a month. She’s been falsely accused of murder, and one of her best friends has already died in the war between the Earth and the elemental world. Besieged on all sides, Ali must defend humanity from the Entity and the Shaktra. But she’s running out of time …
Only the Yanti can stop the horror that is to come. Unfortunately, the talisman is a two-edged sword; it can heal and it can kill. The first time Ali tries to use it as a weapon, it nearly destroys her. If Ali Warner cannot solve the riddle of the Yanti, the Earth, as well as the elemental kingdom, are doomed.