Hydaelyn is the central deity in the lore of Final Fantasy XIV, representing light and harmony. She is often depicted as a guiding force for the inhabitants of the realm, known as Eorzea, and is in constant conflict with her counterpart, Zodiark, who embodies darkness and chaos. As the Mothercrystal, Hydaelyn is not only a source of power but also a protector of the world. Her influence is felt throughout the game, as players embark on quests to uncover the mysteries of her existence and the balance she maintains between light and dark.