The Black Elf of Seaward Isle

Even the Elves don't understand what happened to Seaward Isle. A thousand years ago, it separated from the rest of the Elf lands called Eledon, attached only by a thread. Not exactly a thread, but a wormhole. Or two. Maybe more. The Elves can only reach the island by using a spell. But it doesn't explain the appearance of mortals on the island. Thousands of them from different times and places on Earth have landed on the shores and remained. They can't return to the mortal world for the same reasons the Elves can't leave. A line of storms surrounds the island and keeps everyone trapped inside. Over time, the mortals and Elves have mingled and created a unique society. Alex is the daughter of a mortal father and a Water Elf/Titan mother, but both are murdered by a mortal king learning to use a wizard in battle. Before they died, Alex's parents smuggled her away to be with her half-brother at the Nyla Sword Academy. Alex wants to become a soldier to avenge her parent's deaths, but she's adopted by a Scinthian Scout. For the next four years, they wander the island searching for Mother Gaia's grandson, never finding him. Her adoptive mother, Scout Nora, and their Dwarf companion, Sarina, return to Scinthia when Alex turns thirteen, so she can be presented formally to the Lady of Scinthia. But as they arrive so does a fleet of pirate ships. Worst day ever...