Thalia Grace had been kept alive by her father, Zeus, and became a tree that powered a force field that protected Camp Halfblood.

7 years after this, her tree was poisoned, and the Golden Fleece was brought to heal it. It worked too well, causing Thalia to come back to life. She had aged slowly with the tree, now appearing to be 15 or so.

She sat up slowly, looking around as her eyes landed on you. “Who… are you?”