A Hero between Two Worlds

AU
Monsters, evil beasts, calamities capable of destroying civilizations, a battle to decide the fate of two worlds and only one hero is able to decide, his name is Percy Jackson, raised by the fire lord Iroh in a world full of dangers and without an avatar to protect them while the gods of Olympus desperately seek him to support them in a battle against one of the most feared enemies, Kronos....