Glow

A long time ago, three deities joined together to make a power that controls and balances all of the universe's elements. Gaia, the Goddess and creator of all lives, represented Earth. She brought the power that creates the plants, food, and animals. Poseidon, one of the twelve Olympians, God of the seas and other waters, brought the power to balance the waters. Finally, Hephaestus was invited to help. He was the God of fire, metalworking, forges, and sculpture. These three powerful beings brought their powers together only to learn that they were missing something. One last element. Air. Gaia asked for the assistance of Aeolus, the God and Keeper of Winds, but he was too busy, and did not want to personally contribute to their plan. Therefore, he sent the Anemoi. The Anemoi were wind Gods who each had respective seasons, conditions, and points of the Earth that they had to control.
And so, the Anemoi, the Goddess of Life, the God of Fire, and the Protector of the Seas created an orb. This orb maintained all of their powers and balanced the Earth. Any one of the gods could use the orb's full powers in case of an emergency as a weapon. The plan had worked for years. Only once did they have to use its full power when Olympus was under attack.
The deities realized that they couldn't keep the orb from being abused by the gods, and couldn't protect it on their own, so Gaia created a new species. Almost human, but this species had powers. Powers much like the Gods. These people either had powers to control the earth, water, air, or fire. Gaia wanted to keep the groups separate, but allow the people to feel like they had a place where they belong. She made eye color an indicator for each clan. Gaia, trying to be open-minded, allowed interbreeding, however she didn't allow their DNA to mix different powers together. You only get one.